THE LIBRARY OF THE UNIVERSITY OF CALIFORNIA PRESENTED BY PROF. CHARLES A. KOFOID AND MRS. PRUDENCE W. KOFOID tot > * J^ 1 OR, THE PLAIN WHY AND BECAUSE. FAMILIARIZING SUBJECTS OF USEFUL CURIOSITY AND AMUSING RESEARCH. BY JOHN TIMES, Editor of" Laconics ." "Arcana of Science and Art^ 8fc. 'Its beginning is pleasure, its progress knowledge, and its objects truth and utility." Sir Humphry Davy. Zoological Aeries, LONDON : . LOW, LAMB'S CONDUIT STREET; HURST, CHANCE, AND GO. ST. PAUL'S CHURCH YARD; C. TILT, FLEET STREET ; H. CONSTABLE, EDINBURGH ; WAKEMAN, DUBLIN, MDCCCXXXl, CONTENTS. QUADRUPEDS. B* * >f. The General Subject 3 Pine Marten . 17 u . 4 c #. ^e Hippopotamus s -. 42 Bones . 5 Bear 17 Ratel . . 43 Stomach Clothing . 7 8 Dog . . . Wolf 19 24 Horse . . , Foreign Horses 43 48 Secretions . 8 Jackal 24 British Horse 50 Respiration . 9 Fox 25 Zebra 53 Feeling Eye 10 10 Hygena The Cat Tribe 25 26 Ass Mule 53 54 Muscles 11 Lion 27 Mole 54 The Ape Tribe 12 Domestic Cat 29 Beaver . 56 Bat . . . . 13 Sloth 31 Seal 57 Squirrel . 14 Camel . 31 Ornithoryucus 58 Dormouse 14 Antelope . 33 Walrus 59 Marmot 15 Unicorn . 34 Mermaid . 59 Lemming 15 Chamois . 34 Whale . 60 Porcupine 16 Ox ... 35 Narwhale 64 Hedgehog 16 Giraffe . 35 Dolphin 64 Water Shrew . 16 Deer 36 General Economy of Opossum 17 Fallow Deer . 37 Quadrupeds 65 Ichneumon 17 Swine 38 Domestication 69 Weasel 17 Elephant 39 Fabulous Animals . 70 BIRDS. General Economy . 75 i Redbreast 114 Fly-catcher - 128 Migration 94 Wheatear 115 Tailor-bird 128 BRITISH & EUROPEAN j Martin 115 Gull-tea zer - 128 BIRDS. Swift 116 American Pigeon - J28 Eagle 98 Turtle-Dove . 117 Whip poor Will 129 Hawk . 98 Pigeon 117 Negro Fowl - 131 Owl 99 Rail 118 Curassow 131 Shrike . 102 Partridge 118 Ostrich - 131 Woodpecker . 102 Peacock . 118 Cassowary 132 Kingfisher 103 Heron 119 Spoonbill 133 Dottrel 103 Curlew 119 Horned Screamer - 133 Rook 103 Woodcock 119 Bittern - 133 Raven 105 Ruff- 120 Ibis 133 Magpie . 107 Petrel . 120 Trumpeter 134 Jay ... 107 Swan 12U Darter - 134 Cuckoo . 107 Duck . 121 Tropic Bird - 134 Missel-bird . 108 Hornbill 134 Lark ... 108 FOREIGN BIRDS Grossbeak 134 Swallow . 109 Vulture - 122 Faithful Jacana 135 Starling . 111 Parrot - 123 Bell-bird 135 Crossbill 111 Toucan - 124 Sawing-bird - 134 Bullfinch 111 Americ. Wood pecker 124 Cat- bird 135 Lark 113 Red Creeper - 124 Rice-bird 135 Bunting . 113 Humming Bird 125 Cooly - 136 Chaffinch 113 American Crow 125 Booby - 136 Canary Bird . 113 Bird of Paradise 125 Pelican - 136 Linnet . 113 Indicator 126 Cormorant 137 Sparrow 114 Loxia 126 Man of War . . 137 Nightingale . 114 Mocking-bird - 126 Ornithoryncus 137 Dipper 114 Snow -bunting - 127 General Economy . 13 CONTENTS. AMPHIBIA. General Economy - 147 Crocodile and Ali- Proteus li& REPTILES - - 15:3 The Tortoise Tribe 153 gator - - 156 Chameleon - 160 Serpents Rattlesnake - 161 169 Frog and Toad - 154 Gecko - - 162 Sea-Serpent - 170 FISHES. General Economy - 171 Electrical Fish - 192 Salmon 194 The Shark - - 187 Dory - - - 193 Grayling 197 Saw-fish, Sturgeon, Perch and Stickle- Pike J97 &c. - - 188 back - - 193 Herring, Barbel, &c. 197 Eel ... 189 Mullet - - 494 Angling 199 WORMS. General Economy - 201 Man-of-War - - 208 Oyster 214 The Earthworm - 203 Cuttle-fish - - 209 Mussel 215 Leech - - - 203 Testacea Shells - 211 Pearls 215 Snail - - - 204 Pierce-stone - - 214 Nautilus 216 INSECTS. General Economy - 219 Locust - - 253 Ant-lion 2GU COLEOPTERA. Lantern-fly - 255 HYMENOPTERA. Beetle - 237 Froth -worm - 255 The Gall Insect - 20f others, learn tunes, and can even be made to sing in company, so that it has been possible actually to give a little concert by several bullfinches. In general, however, the song of birds in the wild state, appears to be formed by practice and imitation. Blumenbach. Why cannot birds be so correctly said to sing as to ivhistle P Because natural singing is an exclusive privilege of man. Blumenbach. Why do the notes of different species of birds varyP Because, probably, of the structure of the organs of each species enabling them more easily to produce the 82 KNOWLEDGE FOR THE PEOPLE. notes of their own species, than those of any other, and from the notes of their own species being more agree- able to their ears. These conditions, joined to the fa- cility of hearing the song of their own species, in con- sequence of frequenting the same places, determine the character of the acquired language of the feathered tribes. Fleming. Those who have paid attention to the singing of birds, know well that their voice, energy, and expres- sion, differ as widely as in man ; and, agreeably to this remark, Mr. Wilson, the celebrated ornithologist, says he was so familiar with the notes of an individual wood-thrush, that he could recognise him among all his fellows the moment he entered the woods. Why are birds equally dispersed in spring over the face of the country P Because, during that amorous season, such a jea- lousy prevails between the male birds, that they can hardly bear to be seen together in the same hedge or field. Most of the singing and elation of spirits, of that time, seem to be the effect of rivalry and emula- tion. . White* Why is August the most mute month, the Spring, Summer, and Autumn through P Because many birds which become silent about Midsummer, reassume their notes in September ; as the thrush, blackbird, woodlark, willow-wren, &c. G. White. Why is it inferred that birds possess some notion of power, and of cause and effect P Because of the various actions which they perform. Thus, for example, we have seen the hooded-crow in Zetland, when feeding on small shell-fish, able to break some of the tenderer kinds by means of its bill, aided, in some cases, by beating them against a stone ; but, as some of the larger shells^ such as the buckie and * White's Natural History of Selborne. ZOOLOGY. BIRDS. 83 the wilk, cannot be broken by such means, it employs another method, by which, in consequence of applying foreign power, it accomplishes its object. Seizing the shell with its claws, it mounts up into the air, and then loosing its hold, causes the shell to fall among stones, (in preference to the sand, the water, or the soil on the ground) that it may be broken, and give easier access to the contained animal. Should the first attempt fail, a second or a third is tried, with this difference, that the crow rises higher in the air, in order to increase the power of the fall, and more effectually remove the barrier to the contained morsel. On such occasions, we have seen a stronger bird remain an apparently in- attentive spectator of the process of breaking the shell, but coming to the spot with astonishing keenness when the efforts of its neighbour had been successful, in order to share in the spoil. Pennant mentions similar operations performed by crows on mussels. Fleming. Why do birds congregate in hard iveather P Because, as some kind of self-interest and self-de- fence is, no doubt, their motive, may it not arise from the helplessness of their state in such rigorous seasons ; as men crowd together, when under great calamities, they know not why? Perhaps approximation may dis- pel some degree of cold ; and a crowd may make each individual appear safer from the ravages of birds of prey and other dangers. G. White. Why do long-billed birds grow fat in moderate frosts P Because of the gentle check which the cold throws upon insensible perpiration. The case is just the same with blackbirds, &c. ; and farmers and warreners ob- serve, the first, that their hogs fat more kindly at such times ; and the latter, that their rabbits are never in such good case as in a gentle frost. But when frosts are severe, and of long continuance, the case is soon altared ; for then, a want of food soon overbalances the repletion occasioned by a checked perspiration. I have 84 KNOWLEDGE FOR THE PEOPLE. observed, moreover, that some human constitutions are more inclined to plumpness in winter than in summer. G. White. Why do ive so often fail in rearing young birds P Because of our ignorance of their requisite food. Every one who has made the attempt, well knows the various expedients he has resorted to, of boiled meats, bruised seeds, hard eggs, boiled rice, and twenty other substances that Nature never presents, in order to find a diet that will nourish them ; but Mr. Montagu's failure, in being able to raise the young of the curl- bunting, until he discovered that they required grass- hoppers, is a sufficient instance of the manifest neces- sity there is for a peculiar food in one period of the life of birds. Knapp* Why have birds that live on seeds, a crop P Because they swallow the grains unbroken, and the crop, abounding with glands, softens the seeds, which are thence gradually propelled into the stomach. The latter is in bircls extremely muscular, and so powerful, that, according to the remarkable experi- ments of Reaumur and others, it is able to break nuts and olive kernels, and to wear the impressions on pieces of money as smooth as paper. Blumenbach. Why do voracious birds, when devouring their quarry, swallow bones and feathers, and all matters indiscrimi- nately P Because the bones, feathers, &c. assist to promote digestion. Why do birds swallow little pebbles P Because they assist in the division and subsequent digestion of their food. Physiologists have differed as to the object and use for which stones are thus swallowed. Many have even supposed that it proceeds from stu- pidity. According to my own investigation, it is an indispensable measure of assistance to digestion, by * Journal of a Naturalist, 1829. ZOOLOGY. BIRDS. 85 depriving the seeds swallowed of their vitality, without which they would not yield to the digestive powers. Blumenbach. Why have most nocturnal birds large eyes and ears P Because large eyes are necessary to collect every ray of light, and large concave ears to command the smallest degree of sound or noise. Why are aquatic nocturnal birds, as cranes, ivild- ducks, <$'C. very noisy and loquacious P Because their perpetual clamour prevents them from dispersing, and losing their companions. Why are certain birds called "waders?" Because they usually frequent marshy grounds, and the margin of rivers, and wade among the mud or water. All of them are qualified for flying, hy the size of their wings, and for running, by the length of their legs. Why do some birds stand for a great length of time on one foot only, without much exertion P Because of the length of the toes, and the manner in which they are disposed, joined to the disposition of the body with regard to its centre of gravity. Thus, in the stork, " the surface of the femur, (or thigh-bone,) that articulates (or joins) with the tibia, (or the largest leg bone) has, in its middle, a depression which re- ceives a projection of the latter bones. In bending the leg, this process is lifted out of the depression, and removed to its posterior edge. By this motion the ligaments are necessarily more stretched than during the extension of the leg, in which the process remains in its socket. These ligaments, therefore, preserve the leg extended in the manner of some springs, with- out receiving any assistance from the muscles." Cuvier. Why have many genuine land birds the middle toe con- certed by a web with the outer toe, as far as the first joint P 86 KNOWLEDGE FOR THE PEOPLE. Because the sole of the foot is thus increased, and better adopted for standing or walking on the ground. Why have some birds a claw cut like a saw or short- toothed comb P Because they may comb out or rid their plumage of its vermin. Why do some birds roll themselves in dust P Because it may free them from annoyances, or pre- vent the bites of insects. Knapp. Why has it been asked whether Mahomet and his followers might not take one method of purification from these pulveratrices ? Because it is found from travellers of credit, that if a strict Mussulman is journeying in a sandy desert, where no water is to be found, at stated hours he strips off his clothes, and most scrupulously rubs his body over with sand or dust. G. White. Why are certain birds of a Jlock called sentinels P Because they observe approaching danger, and speedily communicate it to the whole flock. In some cases these sentinels are deceived by false appearances. Dr. Edmonstone, in his " View of the Zetland Isles," gives a very striking illustration of this neglect of the sentinel, in his remarks on the Shag. " Great numbers of this species of the cormorant are sometimes taken during the night, while asleep on the rocks, and the mode of accomplishing it is very ingenious. Large flocks, sit, during the night, on projecting rocks of easy access, but before they commit themselves to sleep, one or two of the number are appointed to watch. Until these sentinels are secured, it is impossible to make a successful impression on the whole body ; and, . tpr surprise them is therefore the first object. With this view, the leader of the expedition creeps cautiously and imperceptibly along the rock, until he gets within a short distance of the watch. He then dips a worsted ZOOLOGY. BIRDS. 87 glove in the sea, and gently throws water in the face of the guard. The unsuspecting bird, either disliking the impression, or fancying, from what he considers to be a disagreeable state of the weather, that all is quiet and safe, puts his head under his wing and soon falls asleep. His neck is then immediately broken, and the party dispatch as many as they choose." Why is the new arrangement of birds called " quinary"? Because it proposes to arrange them in groupes of fives, thus : Raptores, or birds of prey ; Imessores, or perching birds ; Rasores, or gallinaceous birds ; Grallatoresy or wading birds ; Natatores, or web-footed birds. Each of these is divisible into fives ; and again into fives. The details of the arrangement would occupy too much space in the present work ; and for them the reader is referred to several papers on the subj ect by Mr. Vigors, the ingenious secretary of the Zoological Society, who thinks the proposed ar- rangement to be strictly in accordance with the natural varieties of birds. It may be observed here, as a curious fact, that " by far the greater number of the pie and sparrow tribe in this country, and perhaps elsewhere, generally }&y five eggs ; the rook, the crow, the hedge-sparrow, goldfinch, blackbird, thrush, &c. The advocates of the quinary arrangement will doubt- less advance this in corroboration of their system."* Why are some birds called monogamous P Because they pair, (from monogamia, one marriage.) Why are other birds called polygamous P Because they never, unless compelled, confine themselves to individual association. (From poly- gamia, many marriages.) The whole number of birds enumerated by Linnaeus, specifically ; is only 960, while those described by Dr. Latham, in his recently published work, amount to about 5,000. * Jennings' Ornithologia. i 2 88 KNOWLEDGE FOR THE PEOPLE. Why do birds exceed quadrupeds in the quantity oj their respiration P Because they have not only a double circulation and an aerial respiration, but they respire also through other cavities besides the lungs, the air penetrating through the whole body, and bathing the branches of the aorta, or great artery of the body, as well as those of the pulmonary artery. Cuvier. Why is parental affection more obvious in birds than in other animals P Because most of their young remain in the nests, wherefore the parents have no cessation of labour from early morning to the close of eve , till the brood can provide for themselves. The young of beasts, on the other hand, sleep much ; some are hidden in lairs and thickets nearly all the day, others take food only at intervals or stated periods, the parent ruminating, feeding, or reposing, too. Knapp. Why are birds called oviparous P Because they produce their young from the egg, (ovum an egg, and pario to bring forth.) Why is there attached to the upper mandible of all young birds about to be hatched, a horny appendage P Because the birds may more effectually perforate the shell, and thus contribute to their own liberation. This sharp prominence or appendage, becomes op- posed to the shell at various points, in a line extending throughout its whole circumference, about one-third below the larger end of the egg ; and a series of per- forations, more or less numerous, is thus effected by the increasing strength of the bird, weakening the shell in a direction opposed to the muscular power of the little captive, which is thus ultimately enabled, by its own efforts, to break the walls of its prison. In the common fowl, this horny appendage falls off in a day or two after the chick is hatched ; in the pigeon, it sometimes remains on the beak ten or twelve days : ZOOLOGY. BIRDS. 89 v^jus arises, doubtless, from the young pigeons being fed by the parent bird some time after being hatched ; and thus there is no occasion for the young using its beak to pick up food. This singular fact was first noticed by Mr. Yarrel, a clever contributor to the Zoological Journal. Why are the eggs of birds enclosed in a shell P Because the shell or calcareous coating, which con- sists of carbonate and phosphate of lime, is to unite with the white of the egg, and form, during incuba- tion, the feathers and bone of the future young ones ; but, as a large portion of this covering remains after the young are produced, its other object is to guard from injury the parts within. Knapp. Why is it puzzling to identify the eggs of birds when detached from their nests P Because the eggs vary so much, and the colourings and markings differ greatly in the same species, and even nest. Why is it concluded that the colouring matter on the shells of eggs does not contribute to the various hues of the plumage P Because, though the calcareous matter is partly taken up during incubation, the markings upon the eggs remain little injured, even to the last, and are almost as strongly defined, as when the eggs are first laid. Again, eggs entirely white will produce birds with a variety of plumage. Knapp. Why is artificial incubation but seldom successful P Because of the great difficulties in graduating the heat properly. For a Table of the respective periods, see Branded Journal, 1829. Why do stale eggs float upon water P Because, by keeping, air is substituted for a portion of the water of the egg, which escapes. Prout. i 3 90 KNOWLEDGE FOR THE PEOPLE. Why has the breast -bone of all birds which fy, a long ridge or keelP Because muscles are attached to it, to facilitate their flight. Why has it been playfully said that birds pair on Valentine 1 s Day p Because, however puerile the notion itself may be, it is certain that about the above period, or sooner or later in the spring, many birds cease their gregarious association, and meet only in pairs for incubation and rearing their young. Why is it thought that the songs of birds are the effect of pleasurable sensations P Because most birds sing only during fair weather. Some of them will occasionally sing even during wet weather : many of the thrush tribe do so. Mr. Bowles illustrates this in the following simile : As some lone bird at day's departing hour, Sings in the sunbeam of the transient shower, Forgetful though its wings be wet the while. Wliy does one sex only of birds sing P Because as Buffon supposed, of cheering his mate during the period of incubation ; but this idea, gallant as it is, has but slight foundation in probability: and, after all, perhaps, we must conclude, that, listened to, admired, and pleasing as the voice of many birds are, either for their intrinsic melody, or from association, we are uncertain what they express, or the object of their song. The singing of most birds seems entirely a spontaneous effusion, produced by no exertion, or occasioning no lassitude of muscle, or relaxation of the parts of action. In certain seasons and weather, the nightingale sings all day and most part of the night ; and we never observe that the powers of song are weaker, or that the notes become harsh and un- tuneable, after these hours of practice. The cuckoo is probably the only bird that seems to suffer from the use of the organs of \oice. ZOOLOGY. BIRDS. 91 Why do birds sing comparatively louder than man? Because the strength of the larynx, and of the mus- cles of the throat in birds is infinitely greater than in the human race. The loudest shout of the peasant is but a feeble cry, compared with that of the golden- eyed duck, the wild-goose, or even the woodlark. Birds of one species sing in general very like each other, with different degrees of execution. In the thrush, however, it is remarkable, that there seem to be no regular notes ; each individual piping a voluntary of his own. Knapp. Why do most of our little songsters , when captured as old birds, become in confinement sullen and dispirited P Because want of exercise and of particular kinds of food, and their changes, alter the quality of their fluids : they become fattened, and indisposed to action, by re- pletion ; fits and ailments ensue, and they mope and die. Knapp. Why is it reasonable to conclude that the notes used by birds, and the voices of animals, are the same as ut- tered by the earliest progenitors P Because, could we find a people, from Japan to the Pole, whose progress in mind has been stationary, with- out increase of idea, from national prej udice or impos- sibility of communication with others, we should pro- bably find little or no alteration in the original lan- guage of that people : so, by analogy of reasoning, the animal having no idea to prompt, no new want to ex- press, no converse with others for a note caught and uttered, is merely like a boy mocking a cuckoo ; so no new language is acquired. This fact is also corro- borated by various little scraps of intelligence scattered through the sacred and ancient writings. With civil- ized man all is progressive ; with animals, where there is no mind, all is stationary. Knapp. 92 KNOWLEDGE FOR THE PEOPLE. Why have bird that feed on grain and seeds a gizzard P Because the gizzard, being covered with very strong muscles, by its action, comminutes the food. Other birds, that are carnivorous or piscivorous, have a sto- mach more resembling that of carnivorous quadrupeds; the digestion of such birds being more accelerated by the gastric juice than by the action of the stomach it- self. Why are hedge fruits, as hips and haivs, sometimes refused by birds? Because the summer has been ungenial, the berries have not ripened well, but have been nipped by frost, and hang on the sprays, dark in colour, small, and juiceless in substance. Why is it best to feed very small birds with meat? Because animal food most readily assimilates with the fluids of their bodies, with the least efforts of the digestive powers. Why do many birds sleep on trees P Because the motion of the branches produced by the wind, increases their disposition for sleep. This may be exemplified in the common fowl : for, placing its bill under the wing, even in broad daylight, and sway- ing it to and fro in the hand for a very short time, will produce sleep ; a beautiful proof of the adaptation of birds to the function. Jennings. Why do not birds fall down in sleeping on their per eh P Because such is the structure of their feet and legs, that the greater the weight upon the muscles, the more firmly the claws grasp whatever they lay hold of. Why does the signal of danger among birds seem to be of universal comprehension P Because, the instant that it is uttered, we hear the whole flock, though composed of various species, repeat a separate moan, and away they all scuttle into the bushes for safety. Knapp. ZOOLOGY. BIRDS. 93 Why is the eagle and some other birds enabled to bear the strongest light of the sun? Because it has a membrane (see page 8. ) with which the bird can, at will, cover the pupil of the eye, while the eyelids remain open. Why are aqueous birds better supplied with food than those on land? Because fish, the food of the former, are probably but little influenced by season ; while our poor land birds find theirs to be nearly annihilated in some cases. Why is the plumage of aquatic birds kept dry P Because the small feathers next the bird fall over each other like the tiles of a roof, and thus throw off the water. Paley tells us that "the laminae or layers of the feathers of birds are kept together by teeth that hook into each other, c as a latch enters into the catch, and fastens a door.' " Why have birds two united glands on the rump P Because these glands secrete a mucous oil, which can be pressed out by the bill of the bird, to anoint its feathers, and replace them when they are discomposed. Aquatic birds have their feathers dressed with this oil from first leaving the shell, but the feathers of other birds are pervious to every shower. Thomson thus al- ludes to this oleous unction : " The plumy people streak their wings with oil, To throw the lucid moisture off." Why have birds the pip P Because the oleous glands just described, become diseased and swollen. It is generally remedied by a single puncture, by which the collected fluid may be discharged. Jennings'* Ornithologia. Why do dab-chicks, moor-hens, and coots, fly erect, witli their legs hanging doivn, and hardly make any dis- patch P 94 KNOWLEDGE FOR THE PEOPLE. Because their wings are placed too forward out of the true centre of gravity ; as the legs of auks and divers are situated too backward. G. White. Why do penguins^ and birds of the same group walk nearly upright P Because the legs are placed farther hack than in other birds. Why is the ancient custom of giving parish rewards for the destruction of small birds as vermin, still con- tinued P Because it may have been requisite in former times, to keep under or reduce the numbers of many preda- ceous animals, which, in a thickly wooded country, with an inferior population, might have been produc- tive of injury ; and we even find parliamentary sta- tutes enacted for this purpose : but now, however, our loss by such means has become a very petty grievance ; our gamekeepers do their part in removing pests of this nature, and the plough and the axe leave but little harbour for the few that escape ; and thus we war on the smaller creatures of creation, and call them vermin. An item passed in one of our churchwardens' accounts, was, " for seventeen dozen of tomtits' heads !" In what evil hour, or for what crime, this poor little bird can have incurred the anathema of a parish, it is difficult to conjecture. The price set upon its head is four-pence per dozen, probably the ancient payment when the groat was a coin. Knapp. MIGRATION. JVhy has the existence of migration been denied ? Because of the surprise, how migrating birds could support themselves so long on wing, as to accomplish their journeys, and at the same time live without food during their voyage. These difficulties, however, vanish altogether if we attend to the rapidity of the flight of birds. Hawks and many other birds probably fly ZOOLOGY. BIRDS. 95 at the rate of 150 miles an hour: an eider-duck at 90 miles an hour : Sir George Cayley computes the common crow to fly at nearly 25 miles an hour ; and Spallanzaiii found that of the swallow about 92 miles, while he conjectures the rapidity of the swift to be nearly three times greater. A falconwhich belonged to Henryl V of France, escaped from Fontainbleau, and in twenty- four hours afterwards was found at Malta, a distance computed to be no less than 1530 miles ; a velocity nearly equal to 57 miles an hour, supposing the falcon to have been unceasingly on the wing. But, as such birds never fly by night, and allowing the day to be at the longest, his flight was perhaps equal to 75 miles an hour. If we even restrict the migratory flight of birds to 50 miles an hour, how easily can they per- form their most extensive migrations! Fair winds may perhaps aid them at the rate of 30 or 40 miles an hour ; nay with three times greater rapidity. Fleming. The migrations of the feathered tribes have been the object of popular observation, since the days of the prophet Jeremiah : " For the stork in the heaven knoweth her appointed times; and the turtle and the crane, and the swallow, observe the time of their coming." ( ch. viii. v. 7.) Why are certain migrating birds called Summer Birds of Passage P Because they arrive in this country in the spring, and depart from it in the winter. Why are other migrating birds called Winter Birds of Passage ? Because they arrive in autumn, and depart in spring. Why may the autumnal shifting of birds, with pro- priety, be termed their Equatorial Migration P Because all those species in which it is observed, move from the Pole towards the Equator, in search of the temperature congenial to their constitutions, and - 96 KNOWLEDGE FOR THE PEOPLE. which the winter of the district of their summer resi- dence could not afford, Fleming. Why may the vernal shifting, with equal propriety be termed the Polar Migration? Because all the species recede with the increasing temperature of the high latitudes of the Equator, and approach towards the Pole. Fleming. Why do certain birds migrate to mild countries on the approach of winter P Because they are unable sufficiently to provide against the vicissitudes of the seasons, by varying the quantity and colour of their dress; but are thus pro- tected by shifting their quarters, so as to live through- out the whole year in a temperature congenial to their constitutions. Fleming. Why are birds sometimes found at sea, in a very ex- hausted state, on the rigging of ships ? Because, in their annual migrations, birds are oc- casionally overtaken by storms of contrary wind, and carried far from their usual course. Mr. White, however, in his Natural History of Sel- borne, says, "It does not appear to me that much stress may be laid on the difficulty and hazard that birds must run in their migrations, by reason of vast oceans, cross-winds, &c. ; because, if we reflect, a bird may travel from England to the Equator without launching out or exposing itself to boundless seas and that by crossing the water at Dover, and again at Gibraltar. And I with the more confidence advance this obvious remark, because my brother has always found that some of his birds, particularly the swallow kind, are very sparing of their pains in crossing the Mediterra- nean ; for, when arrived at Gibraltar, they do not Ranged in figure, wedge their way, and set forth Their airy caravan high over seas ZOOLOGY. BIRDS. 97 Flying, and over lands with mutual wing Easing their flight ; Milton. but scout and hurry along in little detached parties of six or seven in a company ; and sweeping low, just over the surface of the land and water, direct their course to the opposite continent, at the narrowest pas- sage they can find. They usually slope across the bay to the south west, and so pass over opposite to Tangier, which, it seems, is the narrowest space." Why do the periods of the arrival and departure of migrating birds vary in different years P Because they depend entirely on the changes of the seasons. Thus, the meanest rustic, in regard to the summer birds of passage, is aware, that cold weather prevents the arrival of these messengers of spring; and that the early arrival of our winter birds of passage, indicates a proportionally early winter. Why is the arrival of these summer birds to be partly prognosticated by the leafing or flowering of particular trees or plants P Because the same circumstances of temperature which retard the birds, also check the progress of ve- getation. As the state of vegetation depends on the temperature of the season, and the life of the insects, (the food of birds) on the state of vegetation, we may safely conclude, that the movements of the phy tivorous (vegetable-eating) and insectivorous birds must be de- pendent on the condition of plants. Fleming Why is torpidity also called hybernation P Because it is evidently designed to afford animals protection against the cold of winter. Actual torpidity in birds is very rare ; yet the few instances on record establish the fact, while they point to the numerous resources of Nature in extreme cases, to preserve existence. KNOWI [ m.i, ion rm. I>F.MI>I.I . W/ii/ in i- I ///,- mii/ruton/ fords formerly called the Seven ,S7/'/ / uisril \\as theiiMipjMKrd lliat many hirds, which, ;;o\\ known, mit|iiesiionahly migrate, retired to snnir earanee ol' tbrsi- hirds is most likely ean^eil hy s t '\i-iv i'rost Ijavinjr already set in, ai their usual summer re^ideuee. Jennings. }\'hi/ do the bird-eatehers in the neighbourhood of London, procure males i, nit/ on the fir.il arrival of this bird '' Heeause the male^ of many species of mip'ating hirds ;i]>pcar to perform their migrations a few days the females; and this is remarkahly the case with the nightingale. The females do not make their appearance for a week or ten days ai er the males. J''lemin and "pinks?" Because of their constant repetition of one .note, when alarmed or in danger. THE CANARY-BIRD. Why is the Canary-bird so called P Because it was first brought to Europe froan the Canary Islands, about the commencement of the six- teenth century ; but has since deviated into many va- rieties. THE LINNET, Why is the linnet among the least solitary of birds P Because it frequents open commons and gorsy fields, where several pairs, without the least rivalry or con- L3 114 KNOWLEDGE FOR THE PEOPLE. tention, will build their nests and rear their offspring in the same neighbourhood. This duty over, the fa- milies unite, and form large associations, feeding and moving in company, as one united household ; and, resorting to the head of some sunny tree, they will pass hours chattering with each other in a low and gentle note ; and they will thus regularly assemble during any occasional bright gleam throughout all the winter season And still their voice is song, which, heard at some little distance, forms a very pleas- ing concert, innocent and joyous. Knapp. THE SPARROW. Why ought sparrows to be protected P Because a single pair of sparrows, during the time they are feeding their young, will destroy about 4,000 caterpillars weekly. Bewick.- They feed their young also with many winged insects ; in London, it is pre- sumed, chiefly with flies. Jennings. THE NIGHTINGALE. Why are not nightingales heard in Devonshire and Cornwall P Because it is presumed that these birds come over to us from the Continent at the narrowest passage, and do not stroll so far westward. The failure of them in Northumberland and Scotland is, of course, attributable to the want of warmth. G. White. THE DIPPER. Why is a certain bird called the dipper P Because it is enabled to sink to the bottom of the water in pools, and walk thereon, like the hippopotamus among quadrupeds. THE REDBREAST. Why is it said by Pliny, that the redbreast is only so in winter P Because the robin loses nearly all the characteristic ZOOLOGY. BIRDS. 1 15 colour from its breast in the summer, when it moults, and only recovers it on the approach of autumn. Knapp. Why are redbreasts called autumn songsters P Because in spring and summer their voices are drowned and lost in the general chorus ; in autumn their song becomes distinguishable. G. White. Why is the robin the last bird that retires in the evening P Because its fine, large eyes are fitted to receive all, even the weakest, rays of light that appear. The worm is its food too, and few that move upon the surface escape its notice. Why do redbreasts and wrens, in the winter, haunt out-houses, stables, and barns P Because they may there find spiders and flies, that have laid themselves up during the cold season. G. White. THE WHEATEAR. Why is the wheatear highly prized P Because, in an unfortunate hour, it has been called the English ortolan, and is pursued as a delicate morsel through all its inland haunts, when hatching and feeding its young, the only period at which it fre- quents our heaths. Knapp. THE MARTIN. Why do house-martins build their nests only in the morning P Because the work of the nest, chiefly of dirt or loam, may not, while it is soft and green, pull itself down by its own weight, but have sufficient time to harden and dry. G. White. Why do martins usually build to a north-east or north-west aspect P Because the heat of the sun may not crack or de- stroy their nests. G. White. 116 KNOWLEDGE FOR THE PEOPLE. Why are martins less ayile than swallows P Because their wings and tails are shorter, wherefore they are not capable of such surprising turns, and quick and glancing evolutions, as the swallow. G. White. Why is the nest of the house-martin so frequently de- stroyed? Because, in July and August, when it usually brings out its young, one rainy day, attended with wind, will moisten the earthy nest, the cement then fails, and all the unfledged ones are dashed to the ground; and there are some places to which these poor birds are unfortunately partial, though their nests are annually washed down. The parent birds at times seem aware of the misfortune that awaits them ; as, before the ca- lamity is completed, we may observe them, with great anxiety hovering about their nests. Knapp. THE SWIFT. Why is the swift so called P Because it is almost continually on the wing. It eats, drinks, collects materials for its nest, and even propagates on the wing ; thus appearing to live in the air more than any other bird, and performing all func- tions there, save those of sleeping and incubation. In general they feed in a higher district than the other species ; a proof that gnats and other insects do also abound to a considerable height in the air ; they also range to vast distances ; since locomotion is no labour to them, who are endowed with such wonderful powers of wing. Their powers seem to be in proportion to their levers, and their wings are longer in proportion than those of almost any other bird. G. White. Why are swifts out all day long on wet days P Because many insects abide high in the air, even in rain, and the feathers of these birds are well preened to resist the wet.' G. White. ZOOLOGY. BIRDS. 117 Why do sicifts seldom settle on the ground P Because, when down, they can hardly rise, on account of the shortness of their legs and the length of their wings ; neither can they walk, but only crawl. Their bodies being flat, they can enter a very narrow crevice ; and where they cannot pass on their bellies, they will turn up edgewise. G. White. TURTLE-DOVES. Why are turtle-doves emblematic of faithfulness in love? Because of their adoption by the poets ; " as to its highly prized fidelity and chastity, setting aside idle fables, it presents nothing superior to other birds which lead the same mode of life." Blumenbach. The turtle-dove is also called the culver. Spenser, in a sonnet, has Like as the culver on the bared hough, Sits mourning for the absence of her mate. The cooing of the turtle-dove of the United States sounds very melancholy, but is, nevertheless, joyful this being, in reality, the notes of its amorous affection. The dove, in the wild state, breeds twice, but when domesticated, nine or ten times in the year ; so that a single couple would, in four years, produce 14,672. PIGEONS. Why is the carrier-pigeon so called ? Because of the service to which it was formerly ap- plied, particularly in the Levant, of carrying letters. It appears that as soon as young pigeons are hatched, a whitish ash-coloured fluid is secreted in their crop, both in the male and female, in abundance, with which they feed for some time the young before they feed them with grain ; so that, though pigeons' milk would be considered a solecism, yet this fluid seems to be very like milk in its properties. Jennings. Why are such numbers of London pigeons lost during the winter? Because of the slight falcon, which takes up its 118 KNOWLEDGE FOR THE PEOPLE. abode every year, from October and November, until the spring, upon Westminster Abbey, and other churches in the metropolis. THE RAIL. Why is the rail, in Germany, called the King of the Quails P Because it was formerly supposed to head them in their migrations. Why does a partridge sometimes tumble along before a sportsman P Because she may draw away the dog from her helpless covey. G. White. Why is it erroneous to suprjose that black game drive away red grouse ? Because the two species require very different kinds of cover, and will never interfere. Sir W. Jardine. Why are the spurs of cocks of great strength P Because they are supported in the centre by bone. Why are the bones of fowls sometimes of a red tint P Because madder, a plant yielding a red colour, has been mixed with their food. The nature of the food, generally, also exercises a considerable influence over the colour of their bones. THE PEACOCK. Why is it improper to call the long feathers of pea- cocks a tail? Because the feathers do not grow from the^rump, but all up the back. A range of short, brown, stiff fea- thers, about six inches long, fixed in the rump, is the real tail, and props up the long feathers, or train, which is top-heavy when set on end. By a strong muscular vibration, these birds can make the shafts of their long feathers clatter like the shafts of a sword-dancer. G. White. ZOOLOGY. BIRDS. 119 Why were peacocks and pheasants the peculiar food of knights P Because they were said to he the nutriment of lovers, and the viand of worthies. Mills. Why were the highest honours conferred on peacocks ? Because knights associated them with all their ideas of fame, and vowed hy the peacock, as well as by the ladies, to perform their highest enterprises. Mills. THE HERON. Why do herons, in flying, seem encumbered with too much sail for their light bodies P Because of their vast hollow wings, which are ne- cessary in carrying burdens, such as large fishes, &c. G. White. THE CURLEW. Why is the stone-curlew so called P Because, when hatched, the young run immediately from the egg, like partridges, &c. ; and are withdrawn to some flinty field by the dam, where they skulk among the stones, which are their best security ; for their fea- thers are so exactly the colour of our grey spotted flints, that the most exact observer, unless he catches the eye of the young bird, may be eluded. G. White. WOODCOCKS. WJiy do poachers light fires on the coast, to catch woodcocks P Because woodcocks, migrating during the night, and being attracted by the light, bend their course thither; in which manner great numbers are annually des- troyed. Why are the nests of woodcocks and fieldfares so rarely found in England P Because those birds leave us in the spring, in order to cross the seas, and to retire to some districts more suitable to the purpose of breeding. "That the former 120 KNOWLEDGE FOR THE PEOPLE. pair before they retire," observes Mr. White, " and that the hens are forward with egg, I myself, when I was a sportsman, have often experienced." Nat. Hist, of Selborne. THE RUFF. Why is a certain bird called " the Ruff" P Because the neck and ear feathers are much pro- duced in the breeding season, in the males, the heads of which are in part naked. Fleming. THE PETREL. Why were petrels, in past times, thought to predict a storm P Because they seem to repose in a common breeze, but, upon the approach, or during the continuation, of a gale, they surround a ship, and catch up the small animals which the agitated ocean brings near the sur- face, or any food that may be dropped from the vessel. Whisking like an arrow through the deep valleys of the abyss, and darting away over the foaming merest of some mountain wave, they attend the labouring bark in all her perilous course. When the storm subsides, they retire to rest, and are no more seen. Our sailors have, from very early times, called these birds " Mother Gary's Chickens." Knapp. The inhabitants of the Faroe islands use them as lamps : they pass a wick through their bodies, which, when lighted, burns a long time, from the quantity of fat they contain. Blumenbach. THE SWAN. Why has the swan the epithet of mute P Because it utters no sound except its hissing. Why has a " Swan with Two Necks" been adopted as a tavern-sign P Because, it appears, from -the roll of swan's marks in the time of Henry VIII. that the king's swans were ZOOLOGY. BIRDS. 121 double marked, and had what were called two nicks, or notches. The term, in process of time, not being un- derstood, a double animal was invented, with the name of the "Swan with Two Necks." The Mirror, 1828. Why are certain civic excursions on the Thames called " swan-hopping" P Because of its corruption from svf&n-upping, or the taking-up of swans, performed annually by the swan companies, with the Lord Mayor at their head, for the purpose of marking the birds. The Mirror, 1828. Why is a black swan no longer a proverbial rarity P Because it is now found in great numbers in Van Diemen's Land, in New South Wales, and on the western coast of New Holland. The latter settlement, Swan River, has been so named from the flocks of black swans on its banks. Why is the finest down of the eider-duck called " liwP down P Because it is found in the nest: that which is plucked from the dead bird is little esteemed. Eider-down is imported chiefly from Iceland, and other northern countries. It is collected from the nests of birds ; if the nest be deprived of its down, the female takes a fresh quantity from her breast ; but, if the nest be a second time deprived of its down, she cannot supply it ; the male then takes from his breast the necessary lining. Selby. Why have the bills of ducks a soft covering P Because it supplies them with a real sense of taste ; this covering being supplied with exceedingly large cutaneous nerves. Accordingly, it is easy to remark the manner in which ducks probe, as it were, the pud- dles, in search of their food, where they cannot be guided by their sight or smell. Blumenbach. J22 KNOWLEDGE FOR THE PEOPLE. Why do the wedge-like forms of flocks of wild-geese so often change during their flight P Because, it is conjectured, of the leader of the van quitting his post at the point of the angle through fa- tigue, and leaving his place to be filled by another, himself dropping into the rear. Why is the pied oyster-catcher so called P Because it feeds on oysters and limpets, and its bill is so well adapted to force asunder the valves of the one, and of raising the other from the rock, that " the Author of nature," as Derham says, " seems to have framed it purely for that use." FOREIGN BIRDS. Why has it been thought that the tropical regions are deficient in birds of song P Because, from the abundance of the piece tribe, such as parrots, and some others of harsh note, it is probable that their sounds, in the tropical woods, often overpower and confound the more soft and sweet modulations of the warbler tribe. Still, it is a very unfounded notion that in the New World the brilliant hues of the birds take the place of the power of song. On the contrary, it would appear, from Wilson's American Ornithology, that the American song-birds are infinitely more nu- merous than those of Europe, and many of them su- perior to our most celebrated songsters. VULTURES. Why was the vulture held sacred by the Egyptians P Because it was extremely serviceable in destroying mice, lizards, &c. ; whence they have frequently re- presented it in the hieroglyphics on their obelisks, the coverings of their mummies, &c. Blumenbach. Why is a certain species vailed " the King of the vultures" P ZOOLOGY. BIRDS. 123 Because it has been placed at the head of the vul- ture tribe, on account of the superior beauty of its ex- ternal appearance. Waterton, a recent traveller, as- serts, that when the king of the vultures is present, the inferior species do not attempt to touch the prey till the king is satisfied. Why are marine shells to be found buried in the plains , or in the sides of the mountains, of South Africa P Because they have been carried there by birds, and not, as has been generally supposed, by eruptions of the sea. Mr. Barrow, \vho is of this opinion, tells us, in confirmation of it, that " there is scarcely a sheltered cavern in the sides of the mountains that rise imme- diately from the sea, where living shell-fish may not be found any day in the year. Crows even, and vul- tures, as well as aquatic birds, detach the shell-fish from the rocks, and mount with them into the air : shells, thus carried, are said to be frequently found on the very summit of the Table Mountain. In one ca- vern, at the point of Mussel Bay," he adds, " I dis- turbed some thousands of birds, and found as many thousands of living shell-fish, scattered on the surface of a heap of shells, that, for aught I know, would have filled as many thousand waggons." The story, there- fore, of the ancient philosopher, whose bald pate one of these unlucky birds mistook for a stone, and dropped a shell upon, thereby killing at once both fish and phi- losopher, is not so tramontane as to stumble all belief. PARROTS. Why have parrots, in general, striking peculiarities in their manners P Because they have the power of using their feet almost like hands ; as for carrying food to their mouths, scratching behind their heads, &e. When they walk on the ground, they tread not merely on the claws, like other birds, but on the whole of the foot. Their hook- M 2 124 KNOWLEDGE FOR THE PEOPLE. shaped upper mandible is articulated, very moveable, and serves the purpose of a third foot in climbing. Why is the Guinea parrot , in French , called " V in- separable" P Because it has been said, but untruly, that they must always be kept in pairs, a single one not surviving the loss of its mate. Why are many families of parrots found only in dis- tricts of very limited extent P Because their wings are short, and unfitted for long flights. This is, at least, one cause. In the Philip- pines, for instance, many families of parrots are con- fined to particular islands, and never met with on others lying in the immediate vicinity. Blumenbach. THE TOUCAN. Why is the toucan also called the " Egg-sucker" ? Because it chiefly feeds on the eggs found in other birds' nests. Why has the toucan a broad and long bill, covered with branches of nerves P Because the nests in which it finds its food are often very deep and dark, and this provision enables the bird to feel its way as accurately as the finest and most delicate finger could. WOODPECKER. Why is the doivny woodpecker so destructive to the orchards of North America P Because it makes one hole close to another, in a horizontal line, till it has completed a circle of holes all round the tree. RED-CREEPER. Why is the hook-billed red-creeper so highly prized in the Sandwich Isles P Because the ingenious natives manufacture various articles of ornament and dress, as helmets, and even entire mantles, with its carmine red feathers. ZOOLOGY. BIRDS. 125 HUMMING-BIRD. Why are humming-birds so called P Because they are almost continually on the wing, fluttering like bees, and making a humming noise. They are so small as to be worn as ear-rings by the In- dian ladies. When dried, the least of them weigh only about twenty grains each. The nest is of cotton, and about the size of a walnut, with two eggs about as big as peas. AMERICAN CROW. Why does the carrion-crow of America differ mate- rially from the bird so common in England ? Because of its greater rapacity as well as lameness. Thus, in the cities where they are protected, they enter the very kitchen, and feed on whatever is thrown to them, even vegetables. If unmolested, they will remain in the same premises for months, flying to the roof at dusk to spend the night. Six or seven are often seen standing, in cold weather, round the funnel of a chim- ney, apparently enjoying the heat from the smoke. Notwithstanding the penalties imposed by law, a num- ber of these birds are destroyed on account of their audacious pilfering. They seize young pigs as great dainties. They watch the cackling hen, in order to get the fresh egg from her nest ; and they will not hesitate to swallow a brood of young ducks. In order to keep them from the roofs of houses, where their dung is detrimental, the inhabitants guard the top with broken pieces of glass fastened in mortar ; and they often kill them by throwing boiling water upon them. No fewer than two hundred of these birds are daily fed by the city of Natchez. Audubon. BIRD OF PARADISE. W T hy were birds of paradise formerly thought to be without feet? Because they were and are worn as ornaments in M 3 126 KNOWLEDGE FOR THE PEOPLE. India, on account of their beautiful plumage ; and when sold for this purpose, the Passous still cut off the feet. Blumenbach. INDICATOR. Why is the indicator also called the " honey-cuclwo" P Because, like the honey-bear,* it obtains its food from the nests of the wild bees. Why is the indicator protected by the Hottentot sP Because, by its notes, it is said to conduct them to the nests of the wild bees. LOXIA. Why is the pensile loxia of the Cape and Madagascar so called P Because it builds a remarkable nest, in the vicinity of water, in shape almost like a retort, with a depend- ing neck for ingress and egress, and so disposed that the aperture is close to the water. Blumenbach. Why do many birds of warm climates build pendulous nests, which are attached to the extreme branches of trees P Because there only are they secure from their ene- mies, the snakes and monkeys. MOCKING-BIRD. Why is the mocking-bird so called P Because, in addition to the fulness and melody of his original notes, he has the faculty of imitating the notes of all other birds, from the humming-bird to the eagle. In measure and accent he faithfully follows his originals, while in force and sweetness of expression he greatly improves upon them. A byestander might suppose that the whole feathered tribes had assembled together on a trial of skill, each striving to produce his utmost effect, so perfect are his imitations. He often See Quadrupeds, p. 18. ZOOLOGY. BIRDS. 127 deceives the sportsman, and even birds themselves are sometimes imposed upon by this admirable music. In confinement he loses little of the power or energy of his song. He whistles for the dog : Caesar starts up, wags his tale, and runs to meet his master. He cries like a hurt chicken, and the hen hurries about, with feathers on end, to protect her injured brood. He re- peats the tune taught him, though it be of considera- ble length, with great accuracy. He runs over the notes of the canary, and of the red-bird, with such su- perior execution and effect, that the mortified songsters confess his triumph by their silence. His fondness for variety some suppose to injure his song. His imita- tions of the brown thrush are often interrupted by the crowing of cocks ; and his exquisite warblings after the blue-bird, are mingled with the screaming of swal- lows, or the cackling of hens. During moonlight, both in the wild and tame state, he sings the whole night long. The hunters, in their night excursions, know that the moon is rising the instant they begin to hear his delightful solo. Rennie. Mr. Southey, in his notes to Madoc, says, " A negress was once heard to exclaim, ' Please God Almighty, how sweet that mocking-bird sing ! he never tire.' By day and night it sings alike ; when weary of mock- ing others, the bird takes up its own natural strain, and so joyous a creature is it, that it will jump and dance to its own music. This bird is perfectly domes- tic, the Americans holding it sacred. Would that we had more of these humane prejudices in England, if that word may be applied to a feeling so good in itself, and in its tendency." SNOW-BUNTING. Why is the snow-bunting so called P Because it is the only living creature that is found at the height of 2000 feet above the limit of perpetual 128 KNOWLEDGE FOR THE PEOPLE. snow. The snow-finch is found on Caucasus and the European Alps. FLY-CATCHER. Why is the red-eyed fly-catcher in the West Indies called" Tom Kelly" P Because his notes are in short emphatic bars of two, three, or four syllables ; and on listening to his song, you may fancy you hear the words, " Tom Kelly ! whip! Tom Kelly!" very distinctly. Rennie. TAILOR-BIRD. Whp is the tailor-bird so called p Because of the art with which it makes its nest ; sewing some dry-leaves to a green one at the extremity of a twig, and thus forming a hollow cone, which it afterwards lines with feathers. It is found in India, and is smaller than a wren. Blumenbach. GULL-TEAZER. Why is the sea-swallow also called " the yull-teazer" p Because it is frequently seen to pursue and persecute the lesser gulls, till they disgorge their food, which it dextrously catches before it reaches the water. AMERICAN PIGEON, Why are the wild pigeons of America so celebrated P Because of their great power of flight, which enables them, when in need, to survey and pass over an as- tonishing extent of country in a very short time. This is proved by facts known to the greater number of ob- servers in America. Pigeons, for example, have been killed in the neighbourhood of New York, with their crops still filled with rice, collected by them in the fields of Georgia and Carolina, the nearest point at which this supply could possibly have been obtained ; and as it is well ascertained, that, owing to their great power of digestion, they will decompose food entirely ZOOLOGY. BIRDS. 129 in twelve hours, they must have travelled between 300 and 400 miles in six hours, making their speed at an average of about one mile in a minute ; and this would enable one of these birds, if so inclined, to visit the European continent, as swallows undoubtedly are able to do in a couple of days. Such are their numbers, that the air is described as " literally filled with pigeons ; the light of the noon- day becomes dim, as during an eclipse." It may not, perhaps, be out of place to attempt an estimate of the number of pigeons contained in one of those mighty flocks, and the quantity of food daily consumed by its members. The inquiry will shew the astonishing bounty of the Creator in his works, and how universally this bounty has been granted to every living thing on the vast continent of America. We shall take, for example, a column of one mile in breadth, which is far below the average size, and suppose it passing over us without interruption for three hours, at the rate mentioned above, of one mile per minute. This will give us a parallelogram of 180 miles by 1, covering 180 square miles; and allowing two pigeons to the square yard, we have 1,1 15, 136,000 pigeons in one flock ; and as every pigeon consumes fully half-a-pint of food per day, the quantity must be 8,712,000 bushels per day, which is required to feed such a flock. Audubon. THE WHIP-POOR-WILL. Why is a certain American bird called the " Whip- poor-Will"? Because its notes seem pretty plainly to articulate the words whip-poor-will; the first and last syllables being uttered with great emphasis, and the whole in about a second to each repetition ; but when two or more males meet, their whip-poor-will altercations be- come much more rapid and incessant, as if each was straining to overpower or silence the other. 130 KNOWLEDGE FOR THE PEOPLE. On or about the 25th of April, if the season be not uncommonly cold, the whip-poor-will is heard in Penn- sylvania, in the evening, as the dusk of twilight com- mences ; or in the morning, as soon as the dawn has broke. The notes of this solitary bird, from the ideas which are naturally associated with them, seem like the voice of an old friend, and are listened to by almost all with great interest. At first they issue from some retired part of the woods, the glen, or mountain ; in a few evenings, perhaps, we hear them from the adjoin- ing coppice, the garden fence, the road before the door, and even the roof of the dwelling-bouse, hours after the family have retired to rest. Some of the more ig- norant and superstitious consider this near approach as foreboding no good to the family, nothing less than the sickness, misfortune, or death, of some of its mem- bers. Every morning and evening his shrill and rapid repetitions are heard from the adjoining woods ; and when two or more are calling at the same time, as is often the case in the pairing season, and at no great distance from each other, the noise, mingling with the echoes from the mountains, is really surprising. Stran- gers, in parts of the country where these birds are nu- merous, find it almost impossible for some time to sleep ; while, to those acquainted with them, the sound often serves as a lullaby, to assist their repose. To- wards midnight they generally become silent, unless in clear moonlight, when they are heard with little in- terruption till morning. Rennie. This is one of the goat-suckers, which are chiefly American birds. The European species has been mentioned at p. 102. Besides the whip-poor-will, Wa- terton mentions four kinds that have each a peculiar set of notes. One utters, " Who are you, who, who, who are you ?" another, " work away, work, work away ;" another, " Willy come go ;" and another, a large bird, the size of the English wood-owl, " Ha, ha, /OOLOGY. BIRDS. 131 ha, ha, ha, ha, ha;" which sounds are uttered like a person in deep distress, the departed voice of a night- murdered victim. The plaintive cries of all these are uttered throughout the night. NEGRO-FOWL. Why is the negro-fowl so called P Because it has a black skin. It is principally from St. Jago, in the Cape de Verd Islands, where other species of birds are said to present the same peculiarity. Blumen bach . CURASSOW. Why is the curassow improperly so called P Because it has been corrupted from Curajoa, the name of an island where the bird is found in great abundance. THE OSTRICH. Why is the ostrich enabled to run with such celerity P Because his bones, like those of other birds, are hol- low ; he has also air vesicles similar to other birds, which, notwithstanding he cannot leave the earth, enable him, by the assistance of his muscular legs, to run with astonishing swiftness. Why do the feathers of the ostrich differ from those of other birds P Because they have their shaft exactly in the middle, whereas the feathers of other birds have the webs broader on one side than the other. Why does the ostrich lay and hatch her eggs in the sand P Because her form being ill- adapted to that process, she has a natural oven furnished by the sand, and the strong heat of the sun. Why has the ostrich been so long known for its stu- pidity P Because of its mention in the book of Job,xxix. 16, 132 KNOWLEDGE FOR THE PEOPLE. 17 : " She is hardened against the young ones, as though they were not hers : Because God hath de- prived her of wisdom, neither hath he imparted to her understanding." Some accounts exonerate the ostrich from being the most stupid bird in the creation. This has been proved by the experiment of taking an egg away, or by put- ting one in addition. In either case she destroys the whole by smashing them with her feet. Although she does not attend to secrecy in selecting a situation for her nest, she will forsake it if the eggs have been handled. It is also said that she rolls a few eggs thirty yards from the nest, and cracks the shells, which, by the time her young come forth, being filled with maggots, and covered with insects, form the first repast of her infant brood. The male bird is said to take upon himself the rearing of the young. If two cock birds meet, each with a family, they fight for the su- premacy over both ; for which reason an ostrich has sometimes under his tutelage, broods of different ages. General Miller. Each of the ostrich's eggs, of which it lays about thirty, contains as much as twenty -four hen's eggs. Why are young ostriches seldom domesticated, although they soon become attached to those who caress them P Because they are troublesome inmates : for, stalking about the house, they will, when full grown, swallow coin, shirt-pins, and every small article of metal within their reach. CASSOWARY. Why is the Neiv Holland cassowary hunted? Because it abounds with oil, which is used for leather, &c. Its flesh, when cooked, more resembles beef than fowl. It is hunted with dogs, the scull, or the jaw of which, according to Wentworth, it some- times fractures by a single kick. A fine pair of these ZOOLOGY. BIRDS. 133 birds may be seen in the gardens of the Zoological Society. SPOONBILL. Why * 5 the spoonbill so called P Because of its singular bill having the shape of a spoon. Its singularity does not, however, consist merely in its shape, but also in its structure : for it is not hard, like the beaks of other birds, but soft and flexible like leather. Jennings. HORNED SCREAMER. Why has the horned screamer two spurs on each wing P Because it may defend itself against some noxious animals which infest the native regions of this bird the fenny and marshy parts of South America. Not- withstanding this armour it is said that this bird is the most gentle of all animals ; that the male and female are always found in pairs, and that, if one dies, the other does not long survive. BITTERN. Why does the great American bittern emit a strong light from its breast P Because the light, which is equal to that of a com- mon torch, may illuminate the water, so as to enable the bird to discover its prey. American Naturalist. IBIS. Why was the ibis so famed among the ancient Egypt- ians P Because it was the symbol of the overflowing of the Nile, from its arrival, breeding season, and departure, coinciding with the commencement, &c. of the fertil- izing inundation of that river. It has been frequently represented on their hiero- glyphical monuments, and prepared, like the human bodies, in the form of mummies, great numbers being placed in certain vaults. At present it is rather un- common, at least in Lower Egypt. Blumenbach. 134 KNOWLEDGE FOR THE PEOPLE. TRUMPETER. Why is the trumpeter so called P Because of its harsh, uncommon cry, not unlike a child's trumpet, with which it follows people through the streets, in Brazil and Guinea, so that it is difficult to get rid of it. Waterton. DARTER. Why is the darter of Brazil so called P Because it has a very long neck, which the animal can roll up spirally, and by that means dart its head at the fish it wishes to seize. TROPIC BIRD. Why is the tropic bird so called P Because it lives in the open seas between the tro- pics, chiefly on the flying fish. HORNBILLS. Why is the flesh of the Indian hornbill peculiarly aroma tic P Because it feeds on wild nutmegs, which grow abun- dantly in its native place, the Molucca Islands. Why is another species of the above-mentioned bird called the jealous hornbill P Because he feeds the female during her incubation ; and, during his absence in search of food, should he find on his return, the marks of another bird near the nest, he will, it is said, inclose the female in the nest, and leave her to perish. Horsfield. SOCIABLE NEST. . Why is the sociable grossbeak so called P Because it lives in vast tribes, from 800 to 1000 at times, under one common roof, containing their several nests, which are built on a large species of mimosa. INDIAN GROSSBEAK. Why is it popularly believed in India that the baya, or grossbeak lights the chambers of his nest with fire- ZOOLOGY. BIRDS. 135 flies, which he catches alive at night, and confines with moist clay or cow-dung? Because such flies are often found in his nest, where pieces of cow-dung are also stuck ; but, as their light could be of little service to him, it seems probable that he only feeds on them. FAITHFUL JACANA. Why has the jacana the epithet of "faithful ?" Because it is kept by the natives of South America to wander with the poultry, and defend them from birds of prey, which it does by the spurs on its wings ; it never deserts its charge, but brings them home safely at night. BELL-BIRD. Why is the variegated chatterer of South America also called the bell-bird? Because its voice is, for about six weeks only, in De- cember and January, like the noise of a cracked bell. The carunculated chatterer is also called the bell-bird, from its notes being composed of two syllables in an, uttered in a drawling tone, which (Mr.Waterton says) may be heard three miles distant. SAWING BIRD. Why is the Chilian sawing bird so called? Because, with its straight, and serrate, or notched bill, it cuts down fresh vegetables, as with a saw. Why is the cat bird so called? Because it mews like a cat, or rather, like a young kitten. It also imitates the notes of other birds, and attacks snakes. Wilson. RICE BIRD. Wliy is the rice bird so called P Because, in Cuba, it is found in great numbers clur- N 2 136 KNOWLEDGE FOR THE PEOPLE. ing the season of the rice crop ; but no sooner is the rice gathered, than it removes to Carolina, and meets the same harvest in that country, where it remains till the rice season is past. COOLIES. Why do coolies differ from other birds? Because they do not perch, nor leap from branch to branch, nor do they even walk nimbly ; for, resting on the whole length of the leg, they drag the belly after them. At the Cape of Good Hope they are called Mouse Birds, from their soft plumage, and their fre- quently creeping about the roots of trees. Jennings. THE BOOBY. Why is the booby so called ? Because it is an indolent, senseless, and cowardly bird, submitting to all sorts of depredations upon its happiness with indolent imbecility ; yet it is occasion- ally, when much excited, ferocious. The man-of-war bird no sooner perceives it in the air, than it pounces upon it, not to destroy it, but to make it disgorge the fish which it has swallowed, which is caught by the voracious plunderer before it reaches the water. Jennings. THE PELICAN. Why has the pelican a pouch attached to her bill? Because it answers the purpose of a crop, and is used by the bird to contain food both for herself and her young, which, when hatched, are fed with the fishes that have been for some time macerated in the pouch ; this, w ? hen distended, will contain ten quarts. Great numbers of pelicans are killed for their pouches, which are converted by the native Americans into purses, &c. When carefully prepared, the membrane is as soft as silk, and sometimes is embroidered by the Spanish ladies for work-bags, &c. It is used in Egypt by the ZOOLOGY. BIRDS. 137 sailors, whilst attached to the two under chaps, for holding or baling water. Why ivas the pelican formerly thought to feed her young with her blood? Because, in disgorging the food from the pouch for the young, the hird presses the bottom of the sack upon her breast, and thus the contents are discharged.* THE CORMORANT. Why has the cormorant a small sabre-shaped bone at the back of its vertex P Because this bone may serve as a lever in throwing back the head, when the animal tosses the fishes which it has taken into the air, and catches them in its open mouth. This conjecture is by Blumenbach, who, however, observes, that the same motion is performed by some other piscivorous birds, which are not provided with this particular bone. Why ivas the cormorant formerly domesticated in this country P Because it was trained to fish for its owner ; it is still used in China for this purpose. THE MAN-OF-WAR. Why is the man-of-war bird so called P Because it is one of the most formidable tyrants of the ocean. When in flocks, they attack sometimes even man himself. It is said that a cloud of them at- tacked a crew of French sailors upon the Island of Ascension, and, till some of them were struck down, endeavoured to snatch the meat from their hands. Jennings. THE ORNITHORYNCUS. Why is the ornithoryncus said to form the connecting link between the bird and beast P * See the Vignette. N3 138 KNOWLEDGE FOR THE PEOPLE. Because it has a bill like a duck* and paws webbed similar to that bird, but legs and body like those of a quadruped, covered with thick, close hair, with a broad tail to steer by. It is believed to lay eggs ; it bears a claw on the inside of its foot, with a tube therein, through which it emits a poisonous fluid into the wounds which the claw inflicts.* Why have birds a gizzard P Because it may answer the purposes of teeth to mas- ticate their food ; the gizzard being composed of thick and tough muscular substance, small in size, but more powerful in its action than the strongest jaw-bone. It consists of four distinct muscles a large hemispherical pair at the sides, and a small pair at the two ends of the cavity. By their alternate action these muscles produce two effects; the one, a constant friction on the contents of the cavity, the other, a pressure upon them. These muscles are lined with a cuticle which is ex- tremely callous, and which often becomes cartilaginous, and even horny. Reaumur and Spallanzani compelled geese and other birds to swallow needles, lancets, and other hard substances; in a few hours after which, the birds were killed and examined ; the needles and lan- cets were uniformly found broken off and blunted, without the slightest injury having been sustained by the stomach. Swallowing pebbles also aids the action of the gizzard upon the food, the stones in some mea- sure serving the purpose of teeth. Mr. Hunter ob- served that the size of the pebbles is always in propor- tion to that of the gizzards. In the gizzard of a turkey he counted two hundred ; in that of the goose, a thousand. ( See page 84 ) * Cunningham's Sketches of New South Wales. See also QUAD- RUPEDS, page 58 of the present volume. ZOOLOGY. BIRDS. 139 Why does the gastric juice, in its effects, differ in different animals? 'Because of the varieties of food on which they sub- sist. Thus, in birds of prey, as kites, hawks, owls, it only acts upon animal matter, and does not dissolve vegetables. In other birds, and in all animals feeding on grass, it dissolves vegetable matter, as grass, but will not touch flesh of any kind. This has been ascer- tained by making them swallow balls with meat in them, and several holes drilled through, to let the gas- tric j uice reach the meat : no effect was produced upon it. We may farther observe that there is a most curious and beautiful correspondence between this juice in the stomach of different animals, and the other parts of their bodies, connected with the important operations of eating and digesting their food. The use of the juice is plainly to convert what they eat into a fluid, from which, by various other processes, all their parts, blood, bones, muscles, &c. are afterwards formed. But the food is first of all to be obtained, and then prepared by bruising, for the action of the juice. Now, birds of prey have instruments, their claws and beak, for tear- ing and devouring their food, (which is animals of different kinds ) but those instruments are useless for picking up and crushing seeds ; accordingly they have a gastric j uice which dissolves the animals they eat ; while birds which have only a beak fit for pecking, drinking, and eating seeds, have a juice that dissolves seeds, and not flesh. Nay more, it is found, that the seeds must be bruised before the juice will dissolve them : this is found by making the experiment, in a vessel with the juice ; and accordingly, the birds have a gizzard, and animals which graze have flat teeth, which grind and bruise their food before the gastric juice is to act upon it. Why have some birds more air-cells than others? Because the quantity of air which they individually 140 KNOWLEDGE FOR THE PEOPLE. contain, is proportioned to the influence which they exert on the locomotion of the body. Thus, in the eagle, and other birds of long flight, the bones which support the wings are filled with air ; while in such as the puffin, whose wings are unequal to any lengthened flight, or the ostrich, which prefers to run, air-cells are found in the greatest numbers within the bones of the leg and thigh. These air-cells generally exist externally, between the muscles : the bones themselves, which in the mam- malia contain marrow, are, in birds, filled with air. It has also been observed, by Mr. Green, the celebrated anatomist, that, in young birds, a medullary substance is often observable in the bones ; but as they grow up to maturity, it becomes absorbed, and the bone empty. The beauty of this contrivance is equalled only by its importance. Independently of a perfect supply of air being thus furnished at all seasons, for the purposes of respiration, without any inconvenience to the gene- ral system, the relative weight of the body is materially diminished, the difficulty of breathing in a very rare- fied atmosphere is counteracted, and the necessity of a frequent respiration during rapid flight may be dis- pensed with. Why have birds that do not fly wings? Because they assist in balancing the body as they run. Why are the necks of aquatic birds proportionally longer than those of land birds P Because aquatic birds have to seek their food below the surface of the water on \vl>:ch they swim. The length of the neck generally increases in proportion to that of the legs. Blumenbach. Why does the neck of a bird acquire that double bend which makes it resemble the letter S ? - Because the neck joints are not united by plane sur- ZOOLOGY. BIRDS. 141 faces, but by cylindrical eminences, which admit of a more extensive motion, as they also constitute real joints. Four or five of the pieces only bend forwards, while the lower ones are confined to flexion back- wards. Blumenbach. Why do birds stretch out their necks when flying P Because they may become like sharp points, divid- ing the air, and diminishing the resistance. Why are the beaks of birds so diversified in their form and structure. Because each beak is adapted for receiving only certain kinds of food. Thus, some are long and pointed, others are broad and flat ; others are hooked and curved. Why is the freshness of an egg judged by its warmth P Because the egg, like most other living beings, maintains a temperature considerably above that of the surrounding medium ; and, as long as it is alive, it resists putrefaction, under degrees of heat and mois- ture, which cause it to run rapidly into the putrefactive process as soon as it is dead. Why, in several species of birds, have the male and female different plumage P Because, as the female ceases in her old age to lay eggs, she obtains the male plumage. Blumenbach. Why is the body of a newly hatched bird covered with hair instead of feathers P Because little tufts of hair, produced from one com- mon bulb, are the rudiment of the future feather. In a few days a black cylinder appears, which opens at the extremity, and gives passage to the feather. The opposite end receives those blood-vessels, which supply the vessel-like substance in the barrel of the feather ; when the stalk of the feather has received its com- plete growth, this vessel-like body is dried up, and presents the well known appearance called pith, in the barrel of quills. 142 KNOWLEDGE FOR THE PEOPLE. Why are birds considered much less favoured in re- spect to organs of touch than mammalia ? Because one extremity of their bodies is occupied with the bill, and the other with a sort of oar or rud- der. The anterior appendices (or wings) are organs of mere locomotion ; and the remaining portion of the body, or the extremities of the posterior appendices, serve to give them a firm position on their two legs. We find, however, that in these animals the toes are more articulated than in mammalia ; that they are in a great degree capable of being separated from each other ; and the nerves with which they are furnished considerable. It may be inferred, therefore, that the feet of birds would be tolerably perfect organs of touch, if they were not used as organs of locomotion ; and that, the less they are used for the latter purpose, the more perfect is the sense of touch. Accordingly, we find that parrots take up their food with their feet, and convey it to their mouths. In birds of prey the sense is probably more acute, as their feet are little used for progression. In the gallinaceous birds, (as fowls) whose feet are constantly on the ground, and in the ostrich and cassowary, which do not fly, the epidermis (or outer skin) is thickened, and its sensibility conse- quently diminished. Lawrence's Notes to Blumenbach'' s Comparative Anatomy. Why is it erroneous to accuse birds of destroying the buds of trees in spring ? Because it is not the buds, but the insects frequent- ing them, of which the birds are in search. Why are the banks of the Demarara so attractive to ornithologists? Because the birds there are unrivalled in beauty, the birds of Cayenne excepted. Thus, in passing up the river, every now and then, the maam, or tinamou, sends forth one long plaintive whistle, from the depths of the forest, and then stops ; whilst the yelping of the /OOLOGY. BIRDS. 143 toucan, and the shrill voice of the bird called pi-pi-yo, are heard during the interval. The campanero never fails to attract the attention of the passenger ; at a dis- tance of nearly three miles, you may hear this snow- white bird tolling every four or five minutes, like the distant convent-bell. From six to nine in the morn- ing, the forests resound with the mingled cries and strains of the feathered race ; after this they gradually die away. From eleven to three all nature is hushed, as in a midnight silence, and scarce a note is heard, save that of the campanero and pi-pi-yo ; it is then that, oppressed by the solar heat, the birds retire to the thickest shade, and wait for the refreshing cool of evening. At sundown, goatsuckers skim along the trees on the river's bank, and, with owls, lament and mourn all night long. The houtou, a solitary bird, and only found in the thickest recesses of the forest, distinctly articulates " houtou, houtou," in a low and plaintive voice, an hour before sunrise ; the maam whistles about the same hour ; the hannaquoi, pataca, and maroudi, announce the sun's near approach to the eastern horizon ; and the parrots and paroquets confirm his arrival there. Abridged from Waterton's Wander- ings. Why are falcons distinguished as noble and ignoble? Because the noble falcons seize their prey in the air during flight ; for they never devour what has been killed or wounded by other birds ; they must drink the blood of their victims warm or not at all. In all these birds the bill is very short, strong, and much hooked. The ignoble are inferior in many respects ; the tooth of their bills is rounded off, and does not present an acute angle ; while the wings are proportionally short, and consequently weaker. This second grand division of rapacious birds, is seldom, if ever, used in falconry. These definitions are by a correspondent of the Ma- gazine of Natural History, Vol. I. Another writer in 144 KNOWLEDGE FOR THE PEOPLE. that work thinks the term nolle to have been applied, not to all such as take their prey in the air, which de- finition would, he thinks, improperly exclude the ea- gles ; these birds, according to Temminck and Mon- tagu, pouncing their prey on the wing, hut to have been used to denote such as were used in falconry only, which was formerly the sport only of princes and noble persons. Why are the gardens in and about London much more injured by insects, than those in comparatively distant parts of the country P Because, partly, of the smaller number of insecti- vorous birds in and about the metropolis ; and their scarcity is not, as frequently alleged, owing to the smoke, the number of houses, and the want of trees and food, because it is well known that every kind of bird will live, and thrive in cages in the heart of London but to the number of bird-catchers, and, in some respect, the cats. END OF PART IV. LONDON: Printed by C.Richards, St. Martinis-Jane^ Charing -cross. ZOOLOGY. AMPHIBIA. GENERAL ECONOMY. WHY are the bones of reptiles and fishes softer than those of quadrupeds and birds ? Because the former contain much less earthy matter than the latter. In some fishes, the earthy matter is so small, that the cartilage continues, during the whole life of the animal, soft, flexible, and elastic, as the spine of the lamprey ; or a little more indurated (harder) as in the bones of the skate or shark. These fishes have been termed cartilaginous. Even in those fishes which are termed osseous, (or bony,) the cartilage bears a much greater proportion to the earthy matter than in qu adrupeds. Fleming. Why may the circulation of reptiles be considered as imperfect P Because only apart of the blood is aerated, which issues from the heart; and that portion, instead of pro- ceeding directly to the different organs, is again mixed with the circulating fluid. Fleming. Why do Amphibia resemble Mammalia, and differ from Fishes ? Because they breathe with lungs ; although these are of a much looser texture ; and their respiration much more indeterminate, and less regular, than in the two classes of warm-blooded animals. Blumenbach. They are capable of living much longer without respiring, or in a vacuum (as, for instance, toads in cavities, within trees, or blocks of stone) ; they can even B2 H8 KNOWLEDGE FOR THE PEOPLE. endure for a time, an atmosphere of carbonic acid gas ; and there are undoubted proofs of newts and frogs having lived in the stomachs of human beings, or that have recovered, after having been frozen perfectly hard. Why are certain animals, as amphibia and fishes, called cold-blooded ? Because their temperature is greatly influenced by that of surrounding obj ects. In this, and warm-blooded animals, as mammalia and birds, whose temperature is high, and not greatly influenced by the changes in the heat of external ob- jects, the temperature is regulated by the vital powers of the animals; and limits are assigned, beyond which it is dangerous to pass. The range of warm-blooded animals is confined; that of cold-blooded animals extensive. Why have amphibia the remarkable facility and strength of reproduction? Because of the force of their nerves, and the compa- ratively small size of their brain ; as a consequence of which, the nerves are less dependent on the brain ; the whole machine has less mobility, presents fewer indi- cations of sympathy, and the whole life is more simple, and more purely vegetative, than in warm-blooded ani- mals; whilst, on the other hand, the separate parts are endowed with a greater share of peculiar and in- dependent vital power ; whereas, a stimulus applied to one part, or one system of parts, does not, as in warm- blooded animals, excite others by sympathy. We have thus an explanation of the tenacity of life in animals of this class ; (frogs are known to leap about after the heart has been torn out, and tortoises to live for months, after the brain has been removed), and a similar explanation will apply to the long-continued power of motion, in parts of amphibia, when separated from the bodies; as the tails of newts, blindworms, &c. ZOOLOGY AMPHIBIA. 149 As an instance of extraordinary reproduction, Bin- menbach tells us of a large water-newt, one of whose eyes had been entirely extirpated ; notwithstanding which, within ten months, a perfect new eye was formed, with cornea, pupil, lens, &c. and only differing from the eye on the other side, in being about half its size. Why are amphibia considered slow in growth P Because, for example, the frogs of these climates are incapable of producing until their fourth year ; and yet reach what must be considered in proportion to the late period of puberty, the inconsiderable age of from twelve to sixteen years. On the other hand, it is known, that tortoises, even in captivity, have lived up- wards of one hundred years ; so that, by analogy, it may be supposed, that crocodiles, and the large ser- pents, reach a still more advanced age. Blumenbach. Why is the gullet of reptiles usually dilatable P Because their teeth, in general, are fitted for retain- ing their food, rather than for masticating it. One of the most remarkable instances of dilatation, was witnessed in a Boa, brought to Europe in 1817, in the vessel in which Lord Amherst returned from India. This boa, was only about 16 feet long, and 18 inches in circumference ; but, on a live goat being thrust into his cage, he seized the poor creature by the fore-leg, with his mouth, and, throwing it down, it was instantly encircled in his folds ; and, so quickly, that the eye could not follow the rapid motion of his long body, as he wound it round the goat ; its cries became more and more feeble, and at last it expired. The snake, how- ever, long retained his grasp, after it was motionless. He then slowly and cautiously unfolded himself, and prepared to swallow it. He commenced, by cover- ing the dead animal over with his saliva ; and then taking its muzzle into his mouth, he sucked it in as B3 150 KNOWLEDGE FOR THE PEOPLE. far as the horns would allow. These opposed some little dilliculty , but they soon disappeared externally ; yet their progress might be traced distinctly on the outside, threatening every moment to protrude through the skin. The whole operation of completely gorging the goat, occupied about two hours and twenty minutes ; at the end of which time, the tumefaction was confined to the middle part of the body, or stomach ; the superior parts, which had been so much stretched, having re- sumed their natural dimensions. He now coiled him- self up again, and lay quietly in his usual torpid state, for about a month, till his last meal appearing com- pletely digested and dissolved, he was ready for other food, which he devoured with equal facility. Between the Cape of Good Hope and St. Helena, he was, how- ever, found dead in his cage ; and, on dissection, the coats of the stomach were discovered to be excoriated and perforated by worms. Nothing remained of the goat, except one of the horns, every other part being dissolved. A boa, about 9 feet long, was exhibited in London, in 1817. He was fed on live rabbits, ducks, &c., which he also dispatched, by coiling his body two or three times round them, crushing them to death, and then gulping them down by the aid of saliva. Wlii/ are serpents, (as in the case of the boa just men- tioned) enabled to swallow such large bodies iv/iole ? Because the upper jaw is loosely connected with the head ; and, in some species, admits of considerable motion at the point of junction, by which means the mouth can be opened very wide. Why do reptiles crawl ? Because the limbs are placed perpendicular to the mesial line ; and, in the progressive motion, the body is dragged along the ground, as the flexion and ex- tension of the limbs are unable to elevate it above the surface . Fleming. ZOOLOGY AMPHIBIA. 151 Wki/ may animals with many feet be said to glide along a surface P Because their walking is performed by so uniform a motion, the feet not moving by pairs, but by divi- sions, containing from five to twenty, and upwards. The hairs on the rings of caterpillars, it may be here observed, likewise serve as feet, in assisting progressive motion. Whi) have certain reptiles a serpcnti-fonn motion P Because they bring up the tail towards the head, by bending the body into one or more curves, then resting upon the tail, and extending the body, thus moving forward, at each step, nearly the whole length of the body, or one or more of the curves into which it was formed. In serpents, 'this motion is well displayed, whence its name ; and, in some cases, it would appear, that they are assisted in it by means of their ribs, which act as feet. Among the molhisca, (or soft animals) and the annulosa, (or ring-jointed animals) the same kind of motion is performed, by alternate contractions and expansions, laterally and longitudinally, of the whole or parts of the body. The hairs or spines of many of the annulosa, assist their progress ; while in others, the body is so soft and pliable, as easily to ac- commodate itself to the inequalities of the surface over which it glides, and derive assistance from these in its progress. Why do reptiles become torpid during winter P ' Because, chiefly, of the cold acting on a frame ex- tremely sensible to its impressions. During the con- tinuance of a high temperature, they remain active and lively ; but when the temperature is reduced to- wards 40, they become torpid, and in this condition, if placed in a situation where the temperature conti- nues low, will remain torpid for an unknown period of time. Spallanzani kept frogs, salamanders, and snakes, in a torpid state, in an ice-house, where they 152 KNOWLEDGE FOR THE PEOPLE. remained three years and a half, and readily revived when again exposed to the influence of a warm at- mosphere. Why do reptiles respire very slowly during their tor- pidity P Because the circulation of the blood is carried on independent of the action of the lungs. Even in a tortoise, kept awake during the winter by a genial tem- perature, the frequency of respiration was observed to be diminished. The circulation of the blood is diminished, in pro- portion to the degrees of cold. Spallanzani counted from 11 to 12 pulsations in a minute in the heart of a snake, at the temperature of 48, whose pulse in gene- ral, in warm weather, gives about 30 beats in the same period. Dr. Reeves observed the number of pulsations in toads and frogs, to be 30 in a minute, whilst they were left to themselves in the atmosphere, of which the temperature was 53; when placed in a medium, cooled to 40o, the number of pulsations was reduced to 12 within the same period ; and when exposed to a freez- ing mixture at 26, the action of the heart ceased al- together. The powers of digestion are likewise equally feeble. Why has the immediate cause of torpidity in reptiles, been ascertained with more precision than in animals with warm blood P Because this condition with them, does not depend on the state of the heart, the lungs or the brain ; for these different organs have been removed by Spallan- zani, and still the animal became torpid, and recovered according to circumstances. Even after the blood had been withdrawn from frogs and salamanders, they ex- hibited the same symptoms of torpidity, as if the body had been entire, and all the organs capable of action. Why are there but few reptifes in the cold countries of the globe P ZOOLOGY AMPHIBIA. 153 Because they are so easily acted upon by a cold at- mosphere ; while in those countries enjoying a high temperature, they are formed of vast size, of many dif- ferent kinds, and in great numbers. REPTILES. TORTOISE TRIBE. Why are tortoises enabled to bear such immense weights P Because most of them are covered with a firm long- shell, the upper part of which is connected with the spine and ribs, and is covered by the broad horny plates, which in many species are so firm, and of such beautiful colours as to be employed for various pur- poses of art. There are usually thirteen such plates in the middle, and twenty-four round the edges. The under-shell, covering the belly, is somewhat smaller than the upper, with openings for the head, the tail, and the feet. In a Singapore newspaper we read, that the tor- toise, when caught by the Eastern islanders, is sus- pended over a fire, kindled immediately after its cap- ture, until the effect of the heat loosens the shell, so that it can be removed with the greatest ease. The animal, now stripped and defenceless, is set at liberty. If caught in the ensuing season, or at any subsequent period, it is asserted that the unhappy animal is sub- jected to a second ordeal of fire, rewarding its captors this time, however, with a very thin shell. We do not quote this fact for its refinement of cruelty, but to prove the tenacity of life in the tortoise, which must be accounted a very singular fact in na- tural history. Blumenbach observes, that the peculiar and distinct form of this consequently isolated genus, forms a very strong proof of the non-existence of the supposed gra- dation of objects in nature. 154 KNOWLEDGE FOR THE PEOPLE. Why have animals of the tortoise tribe, usually jaws provided ivith a horny covering r , like the bills of birds P Because they are destitute of teeth. Why do these animals deposit their eggs in the sand P Because they may there be hatched by the heat of the sun. A single nest has been known to furnish 500 eggs. Why are the eggs of the land-turtle more likely to be discovered than those of the water-turtle P Because the former leaves its eggs, one by one, as it hobbles over the ground,neither covering nor taking any care of them whatever, nor paying any regard to the offspring. The water turtle, on the contrary, covers its eggs so accurately as to leave no signs perceptible of its nest ; and, however strange it may seem, she so arranges it as to make her tract appear unbroken over the sands, and, after laying her eggs, she proceeds on again in the same direction to complete tlte deception. Why is the flesh of the green turtle so well-tasted, and free from oil ? Because it feeds solely on sea-weeds. It is named from the pale olive-green colour of the shell, and the still more remarkably green colour of its fat. This species sometimes weighs 800 weight. Why is the geometrical tortoise so called P Because its high-arched shell is very regularly marked with black and yellow. FROGS AND TOADS. Why have certain frogs been fabulously said to change into fishes P Because their larva is almost a span long, and then much larger than the perfectly formed animal. The animal also retains its tail for some time after the four legs have acquired their perfect form and size. Why is the tree frog so called P Because it climbs trees in search of insects ; for ZOOLOGY AMPHIBIA. 155 which purpose it has the extremities of the toes ex- panded, with suckers beneath. The clammy slime with which it is covered, like serpents, serves also to support it among the leaves of the trees in which it lives. Why was it formerly believed to rain frogsP Because the young of the common frog living in grass, among bushes, &c. come out in vast numbers, after warm summer showers. Blumenbach. Stories of showers of frogs have, however, obtained credence in our times. Mr. Loudon observes, when at Rouen, in September, 1829, " we were assured by an English family resident there, that during a very heavy thunder shower, accompanied by violent wind, and almost midnight darkness, an innumerable multitude of young frogs fell on and around the house. The roof, the window-sills, and the gravel walks were covered with them. They were very small, but per- fectly formed, all dead ; and the next day being exces- sively hot, they were dried up to so many points or pills, about the size of the heads of pins. The most obvious way of accounting for this phenomenon is by supposing the water and frogs of some adjoining ponds to have been taken up by the wind in a sort of whirl or tornado." Magazine of Nat. Hist. Why does the skin of the frog and toad resemble a bag containing the animal P Because it does not adhere to the subjacent parts, as in other animals, but is attached to them only at a few points, and is unconnected elsewhere. According to old Walton, " the mouth of the frog may be opened from the middle of April till August, and then the frog's mouth grows up, and he continues so for at least six months without eating." Why are toads sometimes found alive inclosed in stones, fyc.P Because the animals have entered a deep crevice of 15(> KNOWLEDGE FOR THE PEOPLE. the rock, and becoming torpid, have been covered with sand, which has afterwards concreted around them. Thus removed from the influence of the heat of spring or summer, and in a place where the temperature con- tinued below the point at which they revive, it is im- possible to fix limits to the period during which they may remain in this torpid state. Such is the explanation of this phenomenon, by Dr. Fleming. An ingenious French naturalist, M. Geoffrey St. Hilaire, thinks it gives a very inaccurate idea of the phenomenon, " to assimilate the state of those be- ings whose lives are preserved in torpidity to the ani- mals benumbed during winter." According to his theory, we must conclude that " there exists, for organi- zation under certain combinations, a state of neutrality intermediate between that of life and death, a state into which certain animals are plunged in consequence of the stoppage of respiration, when it would take place under determinate circumstances." Why is " star -shot jelly " so often seen floating on ponds, $-c. Because frogs are then spawning, and this consists of the glaire which surrounds the eggs, brought into this state by a frog having been swallowed by a bird, and the warmth and moisture of the stomach having made the jelly and the oviducts expand so much, that the bird is obliged to reject it by vomiting. CROCODILE, ALLIGATOR, &C. Why is the crocodile an object of superstitious terror to the Egyptians P Because of its immense size and destructive powers, it being the largest animal inhabiting fresh water, at- taining to full 30, or, as Norclen says, 50 feet in length ; notwithstanding which, its eggs are scarcely as large as a goose's. When full grown, it attacks men and other large animals. When taken young, it may be tamed. The armour, with which the body is covered, ZOOLOGY AMPHIBIA. 157 may be considered as one of the most elaborate pieces of natural mechanism. In the full-grown animal it is so strong as easily to repel a musket-ball, appearing as if covered with the most regular and curiously carved work. Mr. Bullock, late proprietor of a museum in Picca- dilly, saw, at New Orleans, " what are believed to be the remains of a stupendous crocodile, and which are likely to prove so, intimating the former existence of a lizard at least 150 feet long ; for I measured the right side of the under jaw, which I found to be 21 feet along the curve, and four feet six inches wide." The teeth of crocodiles have this peculiarity of structure, that in order to facilitate their change, there are always two, of which one is contained in the other. As a proof of the veneration in which the crocodile was formerly held, we are told by Herodotus, that near Thebes and the Lake Mosris, the natives select one, which they tame, suspending golden ornaments from its ears, and sometimes precious stones of great value ; the fore-feet, however, being secured by a chain. They feed it with the flesh of the sacred victims, and with other suitable food ; and when it dies it is em- balmed, and deposited in a consecrated chest. Various methods are adopted for catching crocodiles. Labat says, " a negro, armed only with a knife in his right hand, and having his left wrapped round with thick leather, will venture boldly to attack the croco- dile in his own element. As soon as he observes his enemy near, the man puts out his left arm, which the animal immediately seizes with his teeth. He then gives it several stabs in the throat, where the skin is very tender ; and the water coming in at the mouth thus involuntarily laid open, the creature is soon de- stroyed." A still more hazardous method was adopted by Mr. Waterton, who travelled in South America 158 KNOWLEDGE FOR THE PEOPLE. about five or six years since. Having secured a cro- codile of the Essequibo, by a baited hook fastened to a long rope, by the aid of some Indians, " I pulled the animal," says the traveller, " within two yards of me ; I saw he was in a state of fear and perturbation ; I instantly sprung up, and jumped on his back ; turning half round as I vaulted, so that I gained my seat with my face in a right position. I immediately seized his fore legs, and by main force twisted them on his back ; thus they served me for a bridle." On his return home, Mr. Waterton published his Travels ; but the jumping on the crocodile was re- ceived by his readers as a traveller's story, till its pos- sibility was established by reference to Pliny's Natu- ral History, where it is stated that the natives of Ten- tyra mount on the crocodile's back " like horsemen, and as he opens his jaws to bite, with his head turned up, they thrust a club into his mouth, and holding the ends of it, they bring him to shore captive, as if with bridles." Other proofs are quoted in the Magazine of Natural History, for 1830. Why does the alligator differ from the crocodile ? Because the body and tail are more round and smooth than the true crocodile ; it is also smaller, and has smaller eggs. Like it, however, it has five toes on the fore feet, and four on the hinder, of which only the three inner ones are provided with claws. Why do alligators swallow stones when going in search of prey ? Because (as the Indians on the Orinoco assert) they may acquire additional weight to aid them in diving and dragging their victims under water. A traveller being somewhat incredulous on this point, Bolivar, to con- vince him, shot three alligators with his rifle, and in each of them were found stones varying in weight according ZOOLOGY AMPHIBIA. 159 to the size of the animal. The largest killed was about 17 feet in length, and had within him a stone weighing about 60 or 70 pounds. Why is the cayman neither safe on land nor in water P Because it is driven into the water by the tiger and other enemies ; whence it is made to scamper ashore by the porpess, the natural enemy and entire master of the cayman; so much so, indeed, that the natives enter the water without fear when the porpess is in sight. Why was the crocodile formerly believed to be van- quished by the ichneumon P Because eggs of crocodiles form the favourite food of the ichneumon, wherefore, this portion of its history became mingled in early times with the above fanciful notion. Divine honours were accordingly awarded to the ichneumon by the ancient Egyptians, and it be- came, and continued for ages, an object of superstiti- ous reverence to a people prone to this symbolical wor- ship of the powers of nature. Ichneumons are still domesticated in Egypt, where they rid the houses of the smaller animals, and per- form the office of our domestic cat. Why may the hippopotamus be classed with am- phibia P * Because it runs with astonishing swiftness, for its great bulk, at the bottom of lakes and rivers. At one time it was not uncommon in the Nile, but now is no where to be found in that river, except above the cataracts. The head of a hippopotamus was brought to Eng- land about four years since, with all the flesh about it, in a high state of preservation. This animal was har- pooned whilst in combat with a crocodile, in a lake in the interior of Africa. The head measures near four * The hippopotamus is, strictly speaking, a quadruped, but its habits being amphibious, entitle it to mention here, especially in connection with the crocodile, to which it is a ferocious enemy. c 2 160 KNOWLEDGE FOR THE PEOPLE. feet long, and eight feet in circumference : the jaws open two feet wide, and the cutting-teeth, of which it has four in each jaw, are above a foot long, and four inches in circumference. This formidable creature, when full-grown, measures about 17 feet long from the extremity of the snout to the insertion of the tail, above 16 feet in circumference round the body, and stands above seven feet high. When excited, it puts forth its full strength, which is prodigious. " I have seen," says a mariner, as we find it in Dampier, " one of these animals open its jaws, and seizing a boat be- tween its teeth, at once bite, and sink it to the bottom". I have seen it, on another occasion, place itself under one of our boats, and rising under it, overset it with six men who were in it, but who, however, happily re- ceived no other injury." Why is a species of lizard called the monitor? Because it is said to keep in company with the cro- codile, and to warn, by its whistling noise, of the proximity of its formidable associate. Why is another species of lizard called the flying dragon P Because it flies or takes short leaps from tree to tree, by having, on each side of the body, a membranaceous wing, scarcely connected with the legs. It is sup- ported by the first six false ribs, which instead of being bent round towards the belly, for the protection of the viscera, proceed laterally from the body. CHAMELEON. Why does the chameleon change colour P Because of the circulation of the blood of the rep- tile, in increased temperature, either of the ambient air or of its own body, producing all the variations of the skin. As the passions of the human mind change the colour of the skin, as well as the form of the features, and according to the rapidity of the flow of blood ; so the feelings of the chameleon may also, in some mea- ZOOLOGY AMPHIBIA. 161 sure, produce analogous changes in the reflecting sur- face of the skin. J. Murray, F.L.S. The reflection of coloured objects on the glittering scales of the chameleon, probably gave origin to the fable that its colour is regulated by that of the bodies near which it is placed. Notes to Blumenbach. Whatever may be the cause, the fact seems to be certain, that the chameleon has an antipathy to things of a black colour. One, which Forbes kept, uniformly avoided a black board which was hung up in the chamber; and, what is most remarkable, when it was forcibly brought before the black board, it trembled violently, and assumed a black colour. It may be something of the same kind which makes bulls and turkeycocks dislike the colour of scarlet, a fact of which there can be no doubt. J. Rennie. Why was the chameleon formerly said to feed on air ? Because its lungs are very large, and by expanding them, the animal can, at pleasure, make itself appear large or small. Why do the eyes of the chameleon differ from those of other amphibia ? Because they can be directed in different ways ; for instance, one upwards and the other backwards ; and that with great rapidity. Why may the mechanism of the tongue of the chame- leon be compared with that of the woodpecker P * Because the chameleon's tongue is contained in a sheath at the lower part of the mouth, and has its extremity covered with a glutinous secretion : it ad- mits of being projected to the length of 6 inches, and is used in this manner by the animal in catching its food, which consists of flies, &c. It is darted from the mouth with wonderful celerity and precision, and the secretion on its extremity entangles the small animals which constitute the food of the chameleon. * See the Woodpecker, page 102. c 3 162 KNOWLEDGE FOR THE PEOPLE. The form of the chameleon's tongue is, however, very different from that of the woodpecker. Notes to J3lu- menbach. GECKO. Why is the gecko so dangerous a reptile in houses P Because it has a poisonous fluid between its scaly toes, which it communicates to the eatables over which it passes. It is common in Egypt, the East Indies, and the South Sea Islands, and even in some parts of Europe, as in the Kingdom of Naples. Why do some lizards climb perpendicular walls, like the common house-fly P Because they have suckers on the under side of the toes, the surfaces of which are broad. They consist of transverse pouches, with fringed margins. THE PROTEUS. Why has the classification of the protcus animal been so much controverted among naturalists P Because its characteristics are equally those of a lizard and a fish. Sir Humphry Davy, in his Consolations in Travel, (to which work we have already referred in Popular Chemistry), describes this extraordinary animal as " a far greater wonder of nature than any of those which the Baron Valvasa detailed to the Royal Society, a century and a half ago, as belonging to Carniola, with too romantic an air for a philosopher." Sir Humphry saw the proteus in a lake, in the beautiful grotto of Maddalena, at Adelsburg, in Illyria. "At first you might suppose it to be a lizard, but it has the motions of a fish. Its head, and the lower part of its body, and its tail, bear a strong resemblance to those of the eel ; but it has no fins ; and its curious bronchial (or lung- like) organs are not like the gills of fishes ; they form a singular vascular (net-like) ^structure, almost like a crest round the throat, which may be removed without occasioning the death of the animal, who is likewise ZOOLOGY AMPHIBIA. 163 furnished with lungs. With this double apparatus for supplying air to the blood, it can live either below or above the surface of the water. Its fore feet resemble hands, but they have only three claws or fingers, and are too feeble to be of use in grasping or supporting the weight of the animal ; the hinder feet have only two claws or toes, and in the larger specimens are found so imperfect as to be almost obliterated. It has small points in place of eyes, as if to preserve the analogy of nature. It is of a fleshy" whiteness, and transparency in its natural state, but when exposed to light, its skin gradually becomes darker, and at last gains an olive tint. Its nasal organs appear large ; and it is abundantly furnished with teeth, from which it may be concluded, that it is an animal of prey ; yet, in its confined state, it has never been known to eat, and it has been kept alive for many years, by occasionally changing the water in which it was placed." Sir Humphry does not think the proteus is bred in the lake in the grotto : " in dry seasons they are seldom found here, but after great rains they are often abun- dant. I think it cannot be doubted, that their natural residence is an extensive, deep, subterranean lake, from which, in great floods, they sometimes are forced through the crevices of the rocks into this place." We have not space for this great philosopher's theory of the proteus ; but we may state its conclusion : " the problem of the re-production of the proteus, like that of the common eel, is not yet solved; but ovaria have been discovered in animals of both species, and in this instance, as in all others belonging to the existing order of things, Harvey's maxim of ' omne vivum ab ovoj (every animal from an egg) will apply." The curious reader should turn to the " Consolations " for Sir Humphry's ingenious speculations on this and many other striking phenomena of nature : indeed, every page of that work is penned in a delightful strain of deep-souled philosophy. 164 KNOWLEDGE FOR THE SERPENTS, Why may the ventral, or belly-plates, or scales of ser- pents, be considered as their feet P Because these scales slide under each other by a kind of inclusion, so as to permit the ventral surface to shorten or lengthen at the will of the animal. When some of the foremost scales are pressed on the ground, those behind are brought forward, and in their turn, supporting the body, enable the forepart to ad- vance. To qualify the scales to do this with greater advantage, they are connected with one another, by means of muscular threads and a longitudinal band, and are likewise aided by the peculiar mechanism of the ribs, which last are connected with the ventral scales by a flexible cartilage. The body, in general, is of a rounded fonn, but, when preparing for progres- sive motion, the ribs are drawn so as to flatten the scales of the belly, and by moving anteriorly or pos- teriorly, give to the scales with which they are con- nected, a corresponding degree of motion. The ribs in this case act as limbs to the scales, which may be compared to feet. This singular use of the ribs of snakes, in assisting progressive motion, was detected by the acute Tyson, and has been still further illus- trated by Sir Everard Home. Fleming. Sir Everard Home was led to this discovery of the aid afforded by the ribs, to the whole tribe of snakes, in the progressive motion of those animals, by the following circumstances. A snake of unusual size, brought to London to be exhibited, was shewn to Sir Joseph Bankes; the animal was lively, and moved along the carpet briskly ; while it was doing so, Sir Joseph thought he saw the ribs move forward in suc- cession, like the ribs of a caterpillar. The fact was readily established, and Sir Everard felt the ribs with his fingers, as they were brought forward: when a hand was laid flat under the snake, the ends of the ZOOLOGY AMPHIBIA. 165 ribs were distinctly felt upon the palm, as the animal passed over it. This was an interesting discovery, as it tended to demonstrate a new species of progressive motion, and one widely different from those already known. Notes to Blumenbach. Of all animals, serpents possess by far the greatest number of ribs ; which amount, in some, to 250 pairs. Why have snakes a bag between the nose and the eye P Because they have no glands to supply the skin with moisture from within, but receive it by coming ill contact with moist substances : it is possible, there- fore, that the bags in the snake may be supplied in that manner, and the more so, as the cuticular lining appears perfect. Another peculiarity is remarkable in snakes so furnished; namely, an oval cavity, situated between the bag and the eye, the opening into which is within the inner angle of the eyelid, and directed towards the cornea, (or transparent membrane to pro- tect the anterior surface of the eye.) In this opening there are two rows of projections, which appear to form an orifice capable of dilatation and contraction. From the situation of these oval cavities, they must be considered as reservoirs for a fluid, which is occa- sionally to be spread over the cornea ; and they may be filled by the falling of the dew, or the moisture shaken from the grass through which the snake passes. Sir E. Home. Why are scales of different colours P Because they derive their colours from the mucus web on which they are placed, and this differs in various animals. The composition of scales, observes Dr. Fleming, is similar to that of the cuticle, with the addition of some earthy salts. They appear to be inserted in that layer of the skin, and to resemble it in many of their properties. When rubbed off, they are easily renewed, and frequently experience the same periodical reno- 166 KNOWLEDGE FOR THE PEOPLE. vations as the cuticle. In reptiles, scales occur on. every part of the body, and are placed laterally in some; whilst in others they are imbricated like the slates of a house. In fishes, the scales are usually imbricated, with the epidermis enveloping their base, and the other edge free. They may also be observed on many insects, exhibiting great varieties of form. What are termed feathers on the wings of butterflies, seem to be a variety of scales. Wliy are serpents said to leap ? Because they fold their bodies into several undula- tions, which they unbend all at once, according as they wish to give more or less velocity to their motion. The body of some serpents is thrown by the mus- cles into a very rigid state, when irritated ; in which condition it breaks into fragments by the slightest stroke. Why do many serpents easily swim P Because they have very long and bladder-like lungs, and the hinder part of the body and tail is much de- pressed. Why do some serpents twist their bodies round the branches of trees, or suffer a considerable portion to hang down P Because, in this attitude, the larger kinds are ready to fall down upon the prey passing beneath, such as deers and antelopes. Such animals are not only re- tarded by their weight, but incommoded by the foe twisting itself in wreaths round their body, and by contractile efforts crushing it to death. Why are serpents so speedily extirpated in civilized countries P Because, not only is man their inveterate personal foe, but he receives powerful support from many of the domestic animals which accompany him in his dispersion over the globe. The hog is not afraid to give battle to the most venomous ; and, in general, ZOOLOGY AMPHIBIA. 167 comes off victorious. The goat likewise readily de- vours the smaller kinds of serpents, and hence the proverb from the Gaelic, " like the goat eating the serpent," importing a querulous temper in the midst of plenty. Fleming. Why are snakes supposed to fascinate other animals ? Because they may more readily entice and secure them for food. Such is the opinion of Professor Silli- man, from his observation of two birds who were en- ticed, and not pursued, by a large black snake in America. " What this fascinating power is," observes the Professor, " whether it be the look or effluvia, or the singing by the vibration of the tail of the snake, or any thing else, I will not attempt to determine possi- bly this power may be owing to different causes in dif- ferent kinds of snakes." Dr. Hancock, in a recent contribution to Jameson's Journal, however, combats this opinion of the fascina- tion of serpents, by saying, " it is not a faculty of charming or of fascinating, in the usual acceptation of the term, which enables certain serpents to take birds ; but, on the contrary, the hideous forms and gestures, which strike the timid animals with impressions of horror, stupefying them with terror, and rendering them unfit for any exertion ; especially as those ser- pents to which has been ascribed the power of fasci- nating, are among the most terrific of the tribe." Why are dragons represented in fable with ringed bodies P Because they originated in the ringed snake, which r even in Europe, has been found ten feet in length and upwards. Its colour is steel- grey, wherefore the dra- gon is often so coloured. Why are venomous serpents distinguishable from those which are not so P Because of the poison-teeth, which are placed on the anterior edge of the upper jaw, with the corres- 168 KNOWLEDGE FOR THE PEOPLE. ponding increase in the size of the latter ; while, in the harmless serpents, the whole of the outer edge of the upper jaw is furnished with teeth, even to the very back part. From the German. Among the other characters of distinction, are the broader and heart-shaped head of the venomous, with small flat scales, instead of a single plate ; the tail-shaped ridge on the back ; and the shorter tail, which measures less than one-fifth of the animal. Dr. Gray, in Philos. Transac. The number of known venomous species, compared to those which are not so, is reckoned as one to six. Why are the fangs of some serpents called poison Because they contain a tubular cavity from their base (where is the poison-bag) passing through a tooth on its convex side, to the apex, where it ends in a nar- row slit. When the serpent bites an animal, the poison flows from the bag through this slit, into the bottom of the wound, where to most advantage it can produce its deleterious effects. The properties of the poison con- tinue even after it has been dried. If instilled into the wound, in any quantity, and it enters any of the larger vessels, death speedily follows. The virulence of the poison depends not only on the species of ser- pent, but on its condition at the time, and the habit of body of the animal which has received the bite. Why is the cobra di capello also called the hooded snake P Because, when irritated, the skin on the neck is ex- panded and drawn forwards, and appears behind the head as a kind of hood. This motion is produced by the cuticular muscles of the neck, aided by the move- able ribs. Why do the snake-catchers of India handle with im- punity the most venomous serpmits P Because they rub their hands ; previously to taking ZOOLOGY AMPHIBIA. 169 hold of the snake, with an antidote composed of pound- ed herbs, the virtue of which is such, that they hold with the naked hand, and provoke fearlessly, the deadly cobra di capello. The secret is not unknown in China ; and the cobra, in common with other serpents of a similar nature, are often exhibited in Canton. Why are vipers distinguished from snakes P Because vipers bring forth their young alive, where- as, snakes hatch their young from eggs, in dung- hills, &c. THE RATTLESNAKE. Why is the rattle-snake so called P Because it has a series of cups appended to its tail ; which cups, when the serpent moves its body, likewise move one upon another, and make a rattling noise, not unlike the folding of dried parchment. This noise is said to be audible at the distance of twenty yards, and is thus useful in giving warning of the approach of the destructive reptile, to which it is attached. Its bite is attended with frightful consequences, as in the following instance : " An emigrant family inadvert- ently fixed their cabin on the shelving declivity of a ledge, that proved a den of rattle-snakes. Warmed by the fire on the hearth of the cabin, the terrible reptiles entered in numbers, and, of course, in rage, by night, into the room where the whole family slept. As hap- pens in those cases, some slept on the floor, and some in beds. The reptiles spread in every part of the room, and mounted on every bed. Children were stung in the arms of their parents, and in each other's arms. Most of the family were bitten to death ; and those who escaped, finding the whole cabin occupied by these horrid tenants, hissing and shaking their rattles, fled from the house by beating off the covering of the roof, and escaping in that direction." Flint's Geo- graphy and History of the United States. 170 KNOWLEDGE FOR THE PEOPLE. Dr. Mead supposes this rattle may serve to bring birds, &c., within the reach of the snakes, from the effect its sound produces. Major Gardner, who had lived long in East Florida, affirms, that the young In- dians of that country, were accustomed to imitate the noise of the rattle-snake, for the purpose of taking squirrels, &c. Blumenbach says, " we are assured by credible eye- witnesses, that squirrels, small birds, &c. fall from the trees on which they stand, into the throat of the rattle- snake below ; the circumstance is not, however, by any means confined to this genus, as it has been remarked in many other serpents of both the Old and the New- World. Rattle-snakes are eaten by hogs and birds of prey. They may also be tamed, and rendered docile." Why is the rattle-snake inaudible in the wet season ? Because, as the cups of the rattle consist merely of dried matter, which, in the dry season, is brought into a condition to make a noise when the animal moves, so, in like manner, the rattle, in the wet sea- son, is soft and mute. THE SEA-SERPENT. Why is the existence of the American sea-serpent no longer credited ? Because of the following exposure of its fraud, as related by Professor Silliman. The first sea-serpent was a steam-boat, which, being established at Boston to coast along the shore, and from its powers and capabilities competent to injure the bu- siness of small boats, was described as a sea-serpent that had been seen off Nahant and Gloucester, and had probably come there to consume all the small fish in the place. This was received by many as a serious account, and believed accordingly. Another sea-ser- pent history arose from the circumstance, that a small sloop, called the Sea-serpent, having been passed by ZOOLOGY FISHES. 171 another vessel, the captain of the latter, when asked, upon his arrival at home, for news, said he had seen a sea-serpent, and then described its bunches on the back, the action of its tail, and other parts ; all of which being understood literally, actually appeared in print, as evidence for the existence of the animal. Then a piece of the skin of the bony scaled pike was taken for part of a sea-serpent's hide. And from such occurrences as these, perhaps, mingled with careless observation of the motions and appearances of por- puses, basking sharks, and balaenopterous whales, ap- pear to have originated every thing that has been said about American sea-serpents. Dr. Fleming thinks it " probable, that many of those stories which have been propagated, regarding vast sea- snakes, have originated in the appearance of some of the larger serpents at sea, where they have been driven by accident. Some of the Asiatic species reside almost constantly in the water, either fresh or salt." In 1 827, Dr. Harwood presented to the Royal Socie- ty an account of a new serpentiform sea animal, which he named the ophiognathus. The specimen is 4 feet f> inches in length, and the jaws open wider than those of any other animal that the Doctor is acquainted with ; not excepting even the rattle-snake. Its entire form indicates that it must possess great swiftness of motion in the waters. FISHES. GENERAL ECONOMY. Why does swimming resemble flying P Because the organs which are employed for both purposes, resemble the oars of a boat in their mode of action ; and, in general, possess a considerable extent of surface and freedom of motion. The former condition enables them to strike the surrounding fluid with an oar of sufficient breadth, to give progressive motion to D2 172 KNOWLEDGE FOR THE PEOPLE. the body ; and the latter permits the same organ to be brought back to its former position for giving a second stroke, but in a different direction, and without offering so great a resistance. The centre of gravity is so placed, that the body, when in action, shall rest on the oars or swimmers, or be brought by certain means to be of the same specific gravity with the water. Why do fish swimP Because they have fins, which balance and keep them level; and tails, which act against the water, and direct them like rudders. The form of the body in fishes, is infinitely more va- ried than in reptiles or serpents. In most, however, the body has a vertical direction, i. c. flattened at both sides ; in some, on the contrary, as the rays, it is hori- zontal, and extended laterally ; in others, as the eel, cScc., it is more rounded ; in some prismatic, or qua- drangular. In all, the head and trunk are con- nected immediately, without being separated by a neck. Blumenbach . Why are the fisheries of Britain so important a por- tion of her resources P Because her limited soil, contrasted with extensive sea-coasts, and numerous rivers and lakes, intimate to her population, the expediency of obtaining a large portion of their sustenance from the waters. These are known to teem with life, and to furnish a supply of agreeable and nourishing food, which may be pro- nounced inexhaustible. Savage nations, as the Kamschatkadales, Brazilians, &c. possess the art of preparing fish in a great variety of ways, even as a kind of flour, bread, &c. With many, as the Islanders of the Pacific Ocean, fishing forms a principal occupation, and a serious kind of study with reference to the ingenious methods and in- struments which they have invented. To a great part of the cultivated world, the taking of the herring, cod, ZOOLOGY FISHES. 173 tunny, &c. is of still greater value. The oil of the shark, cod, and herring, is used for burning in lamps, &c. The inhabitants of the eastern coast of the middle of Asia, clothe themselves with the tanned skin of the salmon. Many parts of other fish are employed for the purposes of art, as the scales of the bleak, for making false pearls. Shagreen is made from the skins of sharks and rays. Why do fishes die almost immediately in the air P Because asphyxia (or suspension of pulsation) is oc- casioned by the sinking of the branchiae, or gills, no longer supported by the interposition of water between their laminae (or layers) ; and this idea has been con- firmed in prolonging the life of fishes, by artificially keeping the lamina) in the state of separation which the water produces. On the other hand, by compress- ing the branchiae under water, similarly to their con- dition in the air, death occurred as quickly as in the latter fluid. Water may act on the respiration of fishes chemi- cally, physically, or mechanically. The latter influence has, however, been but imperfectly attended to. In 1830, M. Fleurens, with the view that water exercises only a mechanical action on their respiration, put several iish into wine. They did not live as in water, but their death was much longer delayed than in air. He ex- plained this action of the wine, by remarking that this liquid contains much less air than water. Why do fishes, ivhcn dead, float on the surface of the water, with the belly uppermost P Because the body being no longer balanced by the fins of the belly, the broad muscular back preponde- rates by its own gravity, and turns the belly upper- most, as lighter, from its being a cavity, and because it contains the swimming bladders, which continue to render it buoyant. White's Natural History of Scl- D3 174 KNOWLEDGE FOR THE PEOPLE. Why have not fishes any voice P Because they have not lungs. Although fishes possess no voice by which they can communicate their sensations to others, some species utter sounds when raised above the water, by expelling the air through the gill-opening when the flap is nearly closed: while others, even under water, as the salmon, utter certain sounds while depositing their spawn ; but for what purpose these sounds are uttered, or by what organs they are produced, we are still ignorant. Fleming. A writer in the Magazine of Natural History tells us, that some tench which he caught in ponds, made a croaking like a frog for full half an hour, whilst in the basket at his shoulder. Why are fishes said to have " true" fins and gills P Because these organs may be distinguished from others to a certain degree analogous in young frogs, &c. The gills are filled with innumerable very deli- cate vessels, and are mostly divided on each side into four layers, which somewhat resemble the beard of a quill, and which are attached at their basis to a corres- ponding number of little bones. Blumenbach. Why are these fins essential to swimming P Because they consist of jointed rays, covered by the common integuments : these rays serve to support the fishes, and approach or separate like the sticks of a fan, and move upon some more solid body as a ful- crum. Thus, in sharks, the rays of the fins behind the gill are connected by a cartilage to the spine. The motions of fish are indeed performed by means of their fins. The caudal, or tail fin, is the principal organ of progressive motion ; by means of its various flexures and extensions, it strikes the water in different directions, but all having a tendency to push the fish forward ; the action resembling, in its manner and effects, the well known operation of the sailor termed ZOOLOGY FISHES. 175 skulling. The ventral and pectoral fins assist the fish in correcting the errors of its progressive motions, and in maintaining the body steady in its position. Bo- relli cut off, with a pair of scissars, both the pectoral and ventral fins of fishes, and found, in consequence, that all the motions were unsteady, and that they reeled from right to left, and up and down, in a very irregular manner. Why are the fins of fishes important to the natural- ist P Because the characters furnished by their position, are employed as the basis of his classification. Thus, by Linnaeus and others, the ventral or belly fins, are considered as analogous to the feet of quadrupeds, &c. Why do medusce sivim, although they have no fins, or oars P Because they vary the form of the body by alternate contractile and expansive movements. We may here observe, that the motions in water caused by sea animals of various descriptions, were noticed at an early period by observers, but it is only of late years that they have engaged the particular attention of zoologists. Why have fishes such extraordinary number and bulk of muscles P Because they may support that great expenditure and exertion, which is a necessary consequence of the peculiar abode, and whole economy of these animals. Blumenba'ch. Why have fishes gills P Because they are calculated to separate air from water, with which it is always united, and bring it into contact with the blood. It is to be observed, how- ever, that many animals which reside in the water, breathe by means of lungs, and are obliged, at inter- vals, to come to the surface to respire, such as whales ; but there are no animals which reside on the land, and 176 KNOWLEDGE FOR THE PEOPLE. are furnished with gills, which are obliged to return to the water to respire. Fleming. Why do those fishes , in which the gill openings are but imperfectly covered, expire soonest when taken from the water P Because the air soon dries the fine plumes of the gills, and obstructs the process of respiration and cir- culation. Why docs respiration by gills differ from that by lungs ? Because the former, as in fishes, introduces the air, which the water holds in solution, through the mouth into the gills, and then expels it again through the branchial aperture ; consequently, not by inspiring and expiring through the same passage, as in those animals which possess lungs. Blumenbach. Why do some fishermen cut the gills with a knife as soon as thejish is taken? Because an injury received by the gills of fishes is attended by a considerable effusion of blood ; and a fish so killed, will keep much longer in a fresh state, than one on which this operation of bleeding has not been performed. Wliy is the surface of the skin of fishes almost al- ways covered with slimy fluid P Because it may protect them from the penetrating influence of the surrounding element. The pores from which this viscous matter is secreted, are frequently visible to the eye in fishes : they are connected with vessels which traverse the body under the skin, and contain the fluid. Fleming. Why are the scales, or rather hard coverings, of such protection to reptiles and fishes P Because these parts possess neither vessels nor nerves ; and, therefore, the whole superficies of the ani- mal's body is insensible, and constitutes a dead medium, ZOOLOGY FISHES. 177 through which impressions are conveyed to the subja- cent living parts. Blumenbach. Why do the scales of fishes differ from hair and -feathers P Because scales are not changed, but are perennial ; and are said to receive yearly an additional layer, from the number of which the age of the animal may consequently be determined. The scales of sea-water fish are bare, but those on coasts or in fresh water are covered with a mucous or slimy membrane. In examining these different appendices of the skin, we perceive that they pass, by insensible degrees, into one another, as hair into spines, horns into nails, scales into shells, and crusts into membranes. They have all one common origin, namely, the skin; and, independent of secondary purposes, they all serve for protection. Fleming. Why is the gullet remarkably short in fishes P Because they have no neck. In some, indeed, the stomach seems to open directly into the mouth. The gullet is, however, capable of great extension, and when the stomach is unable to hold the whole of the prey, which has been seized, a part remains in the gullet until the inferior portion gives way. Fleming. Why is the air-bag or sound considered an article of value P Because this organ in the cod or ling, when salted, forms nourishing and palatable food. But it is chiefly in the manufacture of isinglass, that the sounds of fishes are extensively employed. Sturgeon sounds are chiefly used for this purpose. When in a sound state, the external skin of the air- bag (regarded as possessing strong muscular power) is supposed capable of contraction, so as to condense the air, and enable the animal to sink ; or of extension, so as to allow the air to expand, and aid the animal in rising in the water. 178 KNOWLEDGE FOR THE PEOPLE. Why is isinglass so nutritious? Because it consists almost entirely of gelatine. Why is the air-bladder thought to be unconnected ivith the respiration of fishes P Because tins bladder does not exist in many fishes. Why is the air-bladder believed to be subservient to the motion of fishes p Because it is largest in such fishes as swim with considerable velocity. Why have flat fish large lateral finsP Because they have no air-bladder to enable them to swim. In the shark the absence of the air-bladder is compensated by the size and strength of the tail. Why does the lamprey creep slowly at the bottom of the water P Because it has neither air-bladder nor fins to enable it to swim. Why is the osteology of fishes but little attended to by naturalists P Because the skeleton is more complicated than that of man, and is difficult to prepare and preserve. Fleming. The bones of fishes, when reduced to powder, are mixed up with farinaceous substances, and used in- stead of bread, by some of the northern nations. Why do fishes leap P Because of a violent effort of the caudal fin ; or, ac- cording to some, by bending the body strongly, and afterwards unbending it with an elastic spring. Why are certain fish enabled to fly P Because they have the air-bag of uncommonly large dimensions, wherefore the body has great buoyancy. The pectoral fins are likewise large, and having, by a leap raised themselves above the surface of the water, they continue in the air and move forwards, seldom farther than a hundred yards, by the action of these fins. ZOOLOGY FISHES. 179 Why cannot these fish take long flights P Because the membrane of their fins soon becomes dry, when they again fall into the water. The flying fish generally leave the water to escape from other tish which prey upon them. There is also a species of fish which is capable of climbing, and has been known to raise itself five feet above the surface of the water, and mount up the cre- vices of trees, by means of its various spines. Why have some fish a sucker P Because, it is supposed, by its means the fish at- taches itself to the sides of other fishes, or to the bot- toms of ships, when it is carried forward without any exertion of its own ; and, during storms, adhesion to rocks may save a weak fish from being tossed about by the fury of the waves : other purposes, probably, remain to be discovered. About five years since, a correspondent of the Quar- terly Journal of Science, drew up, in Dublin harbour, a whiting pollack, under whose throat a sea-lamprey had buried its head, and thus firmly attached itself. When separated, the lamprey darted on its prey, to which it again adhered firmly. Why is the eye one of the most important organs which fishes are known to possess P Because it enables them to perceive the approach of their foes, and it is the principal instrument by which they obtain their food. The amateur in fly- fishing often tempts the fish with one kind of fly, but in vain ; and. upon substituting another in its place, of a different form or colour, succeeds in the capture. These motions of fish are all regulated by the eye : hence some fish will bite as readily at a bit of red cloth as at a piece of flesh. Fleming. The eyes of fishes are larger in proportion to the size of their bodies, than in quadrupeds, as we find the eye of the cod-fish equal in size to that of an ox. 180 KNOWLEDGE FOR THE PEOPLE. Why have the ray and shark such extraordinary strength of sight P Because the eye rests on a thin cartilaginous pul- ley, which is attached to the bottom of the orbit, and thus increases its motions. In other fishes, the mo- tions of the eye are confined. Why do notfah sleep P Because they have no eye-lids, nor any membrane to close and cover their eyes, as animals that sleep have. Why is the internal ear ofjishes distinguished from that of the other three classes of red-blooded animals P Because it grows as the fish increases in size, and consequently its magnitude is in the direct ratio of the bulk and age of the animal. Why are fishes supposed to possess a feeling analogous to the sense of touch P Because most of them feel acutely on the abdomen, and in the lips. It is doubtful whether their tongue be an organ of taste, and in what degree it may serve that purpose. Blumenbach. Why is the reproduction ofjishes so enormous P Because, probably, a great number of species live in succession on each other, according to their strength and voracity. The following may convey some idea of the prolific powers of fish : Eggs. Carp . . produces .... 203,109 Cod-fish 3686,760 Flounder 1357,400 Herring 36,960 Mackarel 546,681 Perch . 28,323 Pike 49,304 Roach 81,586 Smelt 38-,278 Sole 100,362 Tench 383,252 The rays and sharks seem to produce but a very limited number. The utmost, stated by different ob- ZOOLOGY FISHES. 181 servers, is 26 and 30. It should be added, that there is no estimated proportion between the number of eggs deposited, and the number of fish which arrive at maturity. The eggs are eagerly sought after by other fishes, by aquatic birds, and reptiles ; and in the young state, they are pursued by their own species, as well as by beings belonging to other classes. Why do fishes materially increase in size, previous to the approach of the spawning season ? Because they may be the better enabled to undergo the fatigues and fastings by which spawning is ac- companied. The muscles then acquire size and strength, especially those connected with the tail, the principal organ of progressive motion, so that the body behind appears plump and round. A great deal of fat is deposited between the muscles, but especially on the belly, the flesh of which is, at this time, of con- siderable thickness. Why does this fatness decrease , as the spawn advances to maturity ? Because the fat is withdrawn for its nourishment ; the belly becomes little else than skin, and while the deluded epicure, upon seeing the large roe, imagines that his fish is in the best condition, it has actually reached the very maximum of worthlessness. When the business of spawning is over, the leanness of the fish then becomes apparent, and the extraordinary muscular exertion which it has undergone, is marked by the leanness of its head and the lankness of its tail. Why do fishes deposit the spawn towards the margin of a river, fyc. P Because in the shallow water the numerous small animals reside, which constitute the most suitable food for the tender fry. Again, the cod and haddock, the mackarel and her- ring, annually leave the deeper and less accessible parts of the ocean, the region of the zoophytic tribe, TART VIII. E 182 KNOWLEDGE FOR THE PEOPLE. and deposit their spawn within that zone of marine vegetation which fringes our coasts, extending from near the high-water mark of neap- tides, to a short dis- tance beyond the low- water mark of spring-tides. Amidst the shelter in this region, afforded by the groves of arborescent fuci, the young fish were wont, in comfort, to spend their infancy ; but since these plants have been so frequently cut down to procure materials for the manufacture of kelp, and the requi- site protection withdrawn, the fisheries have suffered in consequence. Why are fishes caught by baits P Because they are deceived by analogy, considering the identity as perfect, when there are only a few points of resemblance. Fleming. We may observe, that the well-known voraciousness of fishes, the eagerness with which they seize a metal button, or any glittering object the whole art of arti- ficial bait and fly-fishing, all seem to point out the organ of sight, as the principal instrument by which they discover their food. Why do anglers maintain that fly-fishing is not a species of cruelty P Because the hook is usually fixed in the cartilaginous part of the mouth, where there are no nerves; and a proof that the sufferings of a hooked fish cannot be great, is found in the circumstance, that though a trout has been hooked and played for some minutes, he will often, after his escape with the artificial fly in his mouth, take the natural fly, and feed as if nothing had happened; having, apparently, learnt from the experiment, that the artificial fly is not the proper food. Pikes have been caught with four or five hooks in their mouths and tackle which they had broken only a few minutes before. Sir H. Davy, in " Salmonia, or Days on Fly-fishing" ZOOLOGY FISHES. 183 Why are anglers recommended to fish early and late in the summer months P Because, generally, fish do not then feed in the middle of the day, unless the weather be very dark and gloomy during drizzling rain or a light breeze of wind. Why are fishes considered nocturnal animals P Because they are active during the night, and in the day remain in a state of repose. Hence the inha- bitants of islands and coasts, who live on fish, choose the night for catching them. Blumenbach. Why are some fishes said to be amphibious? Because they are capable of living either in fresh or salt water at pleasure. Such fish, in an economical point of view, are extremely valuable, as they furnish to the inhabitants of this and other countries, an im- mense supply of food. The salmon is an instance in Scotland, where from one river, (Tay) 50,000 head of full-sized fish have been procured in one season. To the Greenlanders, their salmon is, perhaps, more va- luable ; as it is dried hard, then broken and pounded, and formed into bread, as well as consumed in a fresh or salted state. Why are fishes generally supposed to attain a great ageP Because the element in which they reside, preserves them from the pernicious influence of sudden changes of temperature : the process of ossification, (or growth of bones) is very slow in them ; their blood is very cold and their primary movements tardy. Accord- ingly, we find the age of the carp has been known to reach 200 years, and the pike to 260. " The marks, however, by which the age of fishes may be deter- mined, remained to be discovered." Fleming, Why does a fish but seldom die a natural death from old age? E 2 184 KNOWLEDGE TOR THE PEOPLE. Because, during every period of its existence, it is surrounded by foes; and when no longer able to exer- cise its wonted watchfulness, or exert its power of de- fence, it falls an easy prey to its more powerful adver- saries. Why are not fishes found in all rivers in mountains P Because they appear to prefer certain altitudes. Thus, in ascending mountains, we may observe, that the fish in the lakes and rivers have their boundaries, as well as the vegetables which cover their surface. Wahlenberg found that the pike and perch disappear- ed from the rivers of the Lapland Alps, along with spruce fir, and when 3,200 feet below the line of per- petual snow. Ascending 200 feet higher, the gwiniad and the grayling, were no longer to be found in the lakes. Higher up still, or about 2,000 feet below the line of perpetual snow, the char had disappeared ; and beyond this boundary, all fishing ceased. Why is fish oil (of the sprat, pilchard, $*c.) very lia- able to become foetid P Because, in general, the oil is obtained from the livers of the fish, in which it is lodged in cells ; but, as it cannot be procured completely from livers by mere boiling, they are allowed to become a little pu- trid, that the oil may be more readily extracted, by the rupturing of the cells. Along with the oil various other impurities are obtained, as bile, gelatinous matter, &c. Why have so many absurd stories been told of showers of fishes P Because it sometimes happens that vivacious fishes, or those capable of surviving a long time out of water, are conveyed to a distance by birds, and left without being killed, on rocks or fields. Fleming. Why are some hinds of fah poisonous P Because of the quality of the food on which they have subsisted. This is only conjecture, but is sup- ported by the history of the mussel and the oyster. ZOOLOGY FISHES. 185 which owe their occasional noxious qualities to the zoophytes on which they feed. The poisonous qualities of some shell-fish are, how- ever, attributed by writers on their dietetic properties, to other causes, as we have already shown. * Why are sea fish sometimes found in fresh water P Because, in forsaking the deep water, and approach- ing a suitable spawning station, they leave the sea alto- gether for a time, ascend the rivers and their tributary streams, and having deposited their eggs, return again to their usual haunts. Even certain species of fish, inhabiting lakes, as the roach, betake themselves to the tributary streams, as the most suitable places for spawning. Why, in stocking fish-ponds, should the transportation of fish take place only in winter P Because fish can bear cold much better than heat. Why are fish, as an article of food, well suited for the young, the weak, and the sedentary P Because it is light, and easily digested; but, for the same reason, it is unsuitable food for those engaged in laborious occupations. Why is it difficult to preserve fish in glass jars, or small ponds P Because a great deal of the oxygen in the air con- tained in the water, is necessarily consumed by the ger- mination and growth of the aquatic plants, and the re- spiration of the infusory animalculae. In all cases, when the air of the atmosphere, or that which the wa- ter contains, is impregnated with noxious particles, many individuals of a particular species, living in the same district, suffer at the same time. Why do fishes perish in water that has been boiled P Because the water is then deprived of its atmosphe- ric air, by means of which fishes carry on their re- spiration. * See DOMESTIC SCIENCE, page 45. 186 KNOWLEDGE FOR TPIE PEOPLE. Why, when fish arc steeped in water , does the whole Jluid becomes luminous ? Because the luminousiiess appears to be caused by the infusory animalcule, with which water abounds. Canton, Phil. Trans. Why are fish said to be'" in season"? Because the milt and roe are then ripening. After the fish have deposited the spawn, the flesh becomes soft, and loses much of its peculiar flavour. This is owing to the disappearance of the oil or fat from the flesh, it having been expended in the function of re- production. When in season, the thick muscular part of the backs, as it contains the smallest quantity of oil, is in- ferior in flavour or richness, to the thinner parts about the belly, which are esteemed by epicures, as the most savoury morsels. Why is the reproduction of fishes involved in great obscurity ? Because the element in which they reside conceals from us the actions which they perform, so that we are unable to point out, ^ith certainty, the uses of the different organs, or the functions which they exercise. Even in the days of Aristotle, the difference in the mode of reproduction between the cartilaginous and the osseous fishes had been observed ; and although many accurate observations have been made by modern zootomists, much still remains to be done, both in the field of observation and dissection. In reference to the reproductive system, fishes may be divided into two classes. Thus, some have the sexes distinct, while in others they are united. Fleming. RAY-FISH. Why do the ray yenus appear to have contributed to the fable of Sirens? Because of a certain similarity of the lower part of their head to the human face. Many species have ZOOLOGY FISHES. 187 also been dried, and metamorphosed by a variety of artifices, into supposed basilisks, &c. Although they lay but one egg at a time, they increase so rapidly, that the ocean, in some spots, actually swarms with them. Their eggs have a horny covering with four points, and are called sea-mice. Blumenbach. Why is the liver of the skate, cod, and some other fishes, remarkably oilt/ ? Because the rest of their bodies is almost destitute of fat. Dr. Monro, calculated that the whole gills of a large skate, presented a surface equal to 2,250 square inches ; or equal to the whole external surface of the human body. SHARKS. Why have most of the sharks very numerous teeth P Because they may supply such as may be lost. The white shark has more than 200, lying on each other in rows, almost like the leaves of an artichoke. Those only, which form the front row, have a perpendicular direction, and are completely uncovered. Those of the subsequent rows are, on the contrary, smaller ; have their points turned backwards, and are covered with a kind of gum. These come through the covering sub- stance, and pass forward when any of the front row are lost. The teeth are at first soft and cartilaginous, but gradually become hard as ivory. The white shark weighs as much as 10,000 pounds, and even whole horses have been found in its stomach. Blumenbach . Voracious as are the habits of sharks, the South Sea islanders are not in the least afraid of them. Portlock, the navigator, says : " I have seen five or six large sharks swimming about the ship, where there have been upwards of 100 Indians in the water: they seemed quite indifferent to them, and the sharks never offered to make an attack on any of these people, and 188 KNOWLEDGE FOR THE PEOPLE. yet at the same time, they would greedily swallow our baits." The perseverance with which sharks follow a vessel at sea, containing 1 a dead body, would prove their nasal organs to be very acute. In a recent voyage from Bombay to the Persian Gulf, the smell of a dead body of an Arab sailor of a crew, attracted several sharks round the ship, one of which, eight feet in length, was harpooned and hauled on board. As a curious fact connected with the natural history of the Bible, we may mention that, in 1828, the Rev. Dr. Scot, of Corstorphine, read before the Wernerian Society, a paper on the great fish that swallowed up Jonah, showing, that it could not be a whale, as often supposed, but was, probably, a white shark. We may observe, that the whale is a gratuitous identity, since the text is " a great fish." (Jonah, c. ii. v. 7.) Why is the hammer-headed shark also called the balance fish. Because it has a long obtuse head with eyes fixed at the extremities, and its mouth in the centre. Unlike other sharks, the above is more remarkable for its struc- ture than size, it being little more than 6 feet in length. Why is the pilot-fish so called P Because it is always found accompanying or pre- ceding the formidable shark. Why is the saw-fish so called P Because it has a broad, sword-like weapon in front of the head, with twenty-four or more teeth inserted into its lateral edges. Why is the sturgeon said to have given rise to the fabu- lous tales of monstrous sea-serpents of the North P Because it often happens that many of them follow in a row one after another. The sturgeon is an import- ant fish as well for its flesh, as for the caviare prepared from its roe. It sometimes weighs nearly 1,000 pounds. Blumenbach . ZOOLOGY FISHES. 189 Why is the. sun-fish so called? Because of the phosphorescent light of the sides and belly of the living fish. It weighs, occasionally, as much as five cwt. Why was the sucking-fish formerly believed able to stop a ship in full sailp Because it can attach itself most firmly, by means of the grooves on the back part of its head, to ships, sharks, &c. Why is a certain fish called the sea-horse? Because of the resemblance of its front part to a horse's head and neck. In dying, it bends itself like an S ; and then resembles the knight, at chess. Why is the sea-dragon so called ? Because it has large and wide pectoral fins, which resemble expanded wings. Why has the economy of the eel so long exercised the ingenuity of naturalists ? Because they have hitherto been unable to establish their mode of generation. Lacepede, the French na- turalist, asserts, in the most unqualified way, that they are viviparous ; but, says Sir H. Davy, " we do not remember any facts brought forward on the subject." Blumenbach says " According to the most correct observations, the eel is certainly viviparous;" for which he quotes Voight's Neues Magazine. Sir Eve- rard Home, by a course of patient investigation, has ascertained that the common and conger eels, as well as lampreys, are hermaphrodites, Why do young eels seek fresh water P Because they prefer warmth, and swimming at the surface in the early summer, find the lighter water warmer, and likewise containing more insects, and so pursue courses of fresh water, as the waters from the 190 KNOWLEDGE FOR THE PEOPLE. land, at this season, become warmer than those from the sea. Sir H. Davy, in his Salmonia, has some interesting observations on this curious subject: " Thus, it is certain, that there are two migrations of eels one up and one down rivers, one from and the other to the sea ; the first in spring and summer, the second in autumn, or early in winter. The first of very small eels, which are sometimes not more than two or two and a half inches long ; the second of large eels, which sometimes are three or four feet long, and which weigh from 10 to 15, or even 20lbs. There is great reason to believe, that all eels found in fresh water, are the results of the first migration ; they appear in millions in April and May, and sometimes continue to rise as late even as July, and the beginning of August. I remember this was the case in Ireland in 1823. It had been a cold, backward summer ; and when I was at Bally- shannon, about the end of July, the mouth of the river, which had been in flood all this month, under the fall, was blackened by millions of little eels, about as long as the finger, which were constantly urging their way up the moist rocks by the side of the fall. Thousands died; but, their bodies remaining moist, served as the ladder for others to make their way ; and I saw some ascending even perpendicular stones, mak- ing their road through wet moss, or adhering to some eels that had died in the' attempt. Mr. J. Couch, in the Linncean Transactions, says, the little eels,Jaccord- ing to his observation, are produced within reach of the tide, and climb round falls to reach fresh water from the sea. I have sometimes seen them in spring, swimming in immense shoals in the Atlantic, in Mount Bay, making their way to small brooks and rivers. When the cold water from the autumnal flood begins to swell the rivers, this fish tries to return to the sea ; but numbers of the smaller ones hide themselves dur- ing the winter in the mud, and many of them form, as ZOOLOGY FISHES. 19 i it were, masses together. Dr. Plot, in his History of Staffordshire, says: "eels pass in the night across meadows, from one pond to another;" and Mr. An- derson, in the Philosophical Transactions, distinctly states, that small eels have risen up the flood-gates and posts of the water- works of Norwich ; and then made their way to the water ahove, though the boards were smooth-planed, and 5 or 6 feet perpendicular. He says, when they first rose out of the water upon the dry board, they rested a little, which seemed to be till their slime was thrown out, and sufficiently glutinous ; and then they rose up the perpendicular ascent, with the same facility, as if they had been moving on a plane surface. There can, I think, be no doubt that they are assisted by their small scales, which, placed like those of serpents, must facilitate their progressive motion : these scales have been microscopically ob- served by Leuwenhoeck." Why is it probable that common eels are often con- founded ivith the conger P Because, as very large eels, after having migrated, never return to the river again, they must, (for it can- not be supposed that they all die immediately in the sea) remain in salt water. The conger eel, it may be added, is found from a few ounces to 100 Ib. in weight. Why is the eel destitute of ventral or belly fins}? Because its form is so entirely equal as to require little balance either one way or the other ; the use of the ventral fins being to balance the fish in the water. Why may an eel be skinned without producing any hole in the situation of the eye ? Because the skin in this and the greater number of fishes, passes directly over the eye without forming any fold ; and in the above case it does not adhere very closely to the eye ; the skin only exhibiting at that place a round transparent spot. Why are some fishes blind P 192 KNOWLEDGE FOR THE PEOPLE. Because of the uniform opacity of the skin in pass- ing over the eye. Why does the skin of the eel turn white ivhen plunged into boiling water? Because of the coagulation of the albumen in which the skin is enveloped. ELECTRICAL FISH. Why is not a benumbing sensation always felt when these Jish are touched P Because the animal appears only to excite it when irritated or otherwise disturbed. Then the fish is ob- served to twist its body, as if about to make a vigorous muscular exertion ; and a benubming sensation is in- stantly felt in the fingers, and even as far as the elbows. The fish is capable of making this benumbing effort many times in succession in the water, as well as in the air, when arrived at maturity, and even previous to the natural period of exclusion from the uterus of the mother. When caught in the net, it gives a shock to the hands of the incautious- fisherman, who ventures to seize it. When concealed in the mud, it is capable of making its most violent efforts; and is able to be- numb the limbs to such a degree, as to throw down the passenger who inadvertently places his foot upon the body. We have already noticed the electrical organs of fishes in connexion with the Voltaic apparatus.* Their structure should be more specially mentioned here, although, to explain this fully would occupy more space than we can devote to the subject, great as is its naturo-philosophical interest. The organs of the tor- pedo (of the ray tribe) are double, and occur in the fore part of the body, one on each side of the cranium, and extend back as far as the gill-openings, occupying the whole skin between the upper and under surfaces. * See POPULAR CHEMISTRY, pp. 40 and 47, PartV. ZOOLOGY FISHES. 193 111 the gymnotus electricus, (or electric eel) the organs occupy scarcely one half of the body of the animal, being two on each side, and extending along the sides and belly, from the head to near the tail. In the silurus electricus, found in African rivers, the structure of the organ is more simple than in the torpedo or gymnotus. It consists of a bed of very fine meshes, which cross each other in every direction, the whole being covered by a membrane, which is itself covered with a layer of fat. The nerves with which the organ is provided, proceed from the eighth pair ; but are not so large in proportion as in the torpedo. Abridged from Fleming's Philosophy of Zoology r , vol. i. THE DORY. Why is the fish doree so 'called ? Because, while living, the colour is very resplendent, and as if d'oree, or gilt ; but Sir Joseph Banks used to say it should be adoree, and that it was the most valu- able of fish because it required no sauce. Why is the John Dory in Venice called the Janitore, or the gate-keeper P Because St. Peter is most commonly designated, among the Catholics, as being the reputed keeper of the keys of heaven ; and out of the mouth of this fish they- believe the Apostle took the tribute-money. Why do some Catholics believe the John Dory to be the fish out of whose mouth St. Peter took the tribute- money P Because the breast of the fish is very much flattened, as if it had been compressed ; but, unfortunately for the credit of the monks, this feature is exhibited by at least twenty other varieties of fish. THE PERCH, ETC. Why is the perch better armed against the attacks of its enemies than most fresh-water fishes P Because its spines, when it attains any considerable PART VIII. F 194 KNOWLEDGE FOR THE PEOPLE. size, protect it from the voracity of other fishes ; and when full-grown, even the pike dares not attack it, though the very young perches are its favourite food. Salamanders, small vipers, and young frogs, serve as food to the perch ; and M. de Lacepede has assured Baron Cuvier that they seize even young water-rats. Several species of water-birds, however, pursue the perch with great avidity. It fears thunder, is afraid of frost and ice, and has internal enemies in intestinal worms ; of which, according to Rudolphi, no less than seven species are found in the body of the perch. This fish is very tenacious of life, and Pennant asserts that it may be carried in dry straw for sixty miles without much danger. Cuvier. Why is the stickleback so fatal to the perch ? Because the former often erects its sharp dorsal spines at the moment the perch is about to swallow it, which stick in the palate or throat. Cuvier. THE MULLET. Why were large red mullets so highly prized by the Roman epicures P Because they were more difficult to be got; not that the larger fish were more delicate. Juvenal says, The lavish slave Six thousand pieces for a mullet gave, A sesterce for each pound. But Apicius gave 8000 nummi, or 641. Us. Sd. for a fish of as small a size as a mullet. SALMON. Why do salmon, which begin to approach the coast and enter the rivers as stragglers about February, in- crease in numbers towards May and June? Because the drought and heat of summer render the streams unfit for their reception. At this period they crowd, in shoals, towards the coast, and roam about the estuaries, until the autumnal floods again entice them to enter the rivers. * ZOOLOGY FISHES. 195 Why do salmon spawn in the shallow gravelly fords at the top and bottom of pools P Because they there make a bed by the parent fish working up against the stream, the spawn being de- posited in the gravel and covered at the same time. The bed sometimes reaches from twelve feet in length to ten in breadth. The process frequently occupies more than a week ; during which the eggs deposited by a single fish sometimes amount to 20,000. This spawning season extends from the end of October to the beginning of February, and, according to very satisfactory evidence, it occurs about the same time throughout all the rivers of the United Kingdom. The eggs of the salmon remain in the gravel for seve- ral months, exposed to the influence of running water. In the course of the month of March, and nearly about the same period in all our rivers, the fry are evolved. When newly hatched, they are scarcely an inch in length, of the most delicate structure, and for a while connected with the egg. Upon leaving the spawning bed, the fry betake themselves to the neighbouring pools, where they speedily increase to two or three inches in length. In April, May, and June, they migrate towards the sea, keeping near the margin, or still water, in the river, and when they reach the estuary, they betake themselves to a deeper and more sheltered course, and escape to the unknown haunts of their race, to return shortly after as grisles, along with the more aged individuals. All these seaward migra- tions of the parent fish and the fry, are influenced and greatly accelerated by the occurrence of the floods in the rivers. Quarterly Review. Why do salmon rise better at the fly when the tide is rising, than when it is falling P Because the turn of the salt water brings up aquatic insects, and perhaps small fish ; and it is supposed that salmon know this, and search for food at a time when it is likely to be found. Salmonia. F2 196 KNOWLEDGE FOR THE PEOPLE. Why are certain rivers "fenced" or the fishing of salmon prohibited during some months of the year ? Because the breeding fish and the helpless fry may be preserved and protected. Why is the par or samlet also called the finger-ling? Because it has large blue or olive bluish marks on the sides, as if they had been made by the impression of \\\Q fingers of a hand. Why do the smallest trouts spawn nearly at the same time with the larger ones? Because, in the physical constitution of these ani- mals, their production is diminished as their food is small in quantity. The ova of the large and small trouts are of the same size ; but in the large trout there are tens of thousands, and in the small one rarely as many as forty. Trouts vary in size, from the great lake trout, weigh- ing above 60lb. or 70lb. to that of the brook, which is scarcely larger than the finger. Why are there supposed to be so many varieties of sea- trout P Because fresh- water trout are somesimes carried in floods to the sea, and come back larger and altered in colour and form, and are then mistaken for new species ; and as each river possesses a variety belonging to it, this, with differences depending upon food and size, will, it is thought, account for the peculiarities of par- ticular fish, without the necessity of supposing them distinct species. The same holds good with regard to salmon. Salmonia. THE GRAYLING. Why was the grayling called by St. Ambrose, " the flower of fishes ?" Because of its agreeable odour, and brilliant co- lours. A fine specimen is thus described : " The belly is silvery, with yellow; and the pectoral, ventral, and anal fins, are almost gold-coloured ; the back gray, ZOOLOGY FISHES. 197 with small black spots ; and the back fin beautifully coloured bright purple, with black and blue spots." In flavour, the grayling is " like the most exquisitely tasted of all our fish, the red mullet." The grayling is supposed to have been introduced by the monks, in the time when England was under the See of Rome, from the rivers that contain it being near the ruins of great monasteries. Thus, the Avon, near Salisbury; the Ure, near Fountain's Abbey; the Wye, near the great abbey of Tintern. &c. There are, however, rivers so situated, wherein the grayling is not found ; for instance, in the Stour, at Canter- bury. THE PIKE. Why is the pike considered one of the most voracious of fishes P Because it devours not only fish, but also amphibia of all kinds, toads, &c. ; many aquatic birds, small quadrupeds, and even crabs. Stones, weighing 5 oz. and upwards, have sometimes been found in the stomachs of pikes, which must have been swallowed by them whole. The Zetlandic fishermen assert, that cod-fish swal- low stones before a storm, to enable them to rest more securely at the bottom of the sea, during the conti- nuance of the agitated waves. Fleming. THE HERRING, BARBEL, ETC. Why is the herring a most important animal in the northern world P Because, though attacked by man, and many ani- mals, as the grampus, gulls, &c., it multiplies with astonishing rapidity. Its great and regular migrations, during summer, along the coasts of Europe, particu- larly the Orcades, Norway, &c. have given employ- ment to many thousand people, from the 12th century. Blumenbach. It is, however, asserted, that " we have no satis- F3 198 KNOWLEDGE FOR THE PEOPLE. factory authority for believing that herrings breed in the northern seas, when they have never yet been ob- served in the real icy seas; nor have they even formed a fishery on the coast of Greenland and Iceland. When they first appear on the coast of Scotland, it is not in shoals, but in small numbers ; and they are then taken with a feather, or fly, and a rod. There is no- thing to indicate a migration from the north ; on the contrary, there is every reason to believe they breed in our own seas : but, both the time of their breeding, and their visits, are irregular and capricious. Much good money has been sunk by erecting buildings, and establishing fishing stations, which the herrings after- wards abandoned." Notes in Science, 1828. Sir Humphry Davy says : " The great supposed migrations of herrings from the poles, to the tempe- rate zone, have appeared to me to be only the ap- proach of successive shoals from deep to shallow water, for the purpose of spawning." Salmonia* In a recent paper, in Jameson's Journal, Major W. M. Morrison supports that view of the migration of gregarious fish, which leads to the supposition, that they do not actually travel from north to south ; but that, in accordance with climate, successive shoals ap- proach the coasts for the purpose of spawning ; and this view he supports by some interesting facts. The nets of Hastings are always cast north and south, in order that they may drift with the ebbing and flowing of the tide, which takes the direction of east and west in that part of the British Channel ; and it is curious, that while those fish which are encumbered with roes, are caught in great numbers on the east side of the nets, they are not met with in a greater proportion than one in about one hundred without roes on the west side. At Cairo, the Arab cooks are said to prepare the her- ring for the table, in such a manner, as to intoxicate the eaters. ZOOLOGY FISHES. 199 Why should the barbel be eaten with great care P Because its roe is poisonous, and lias often given rise to dangerous symptoms when eaten. Why has a species of chcetodon the upper jaw ending in a tube P Because it may, through this tube, throw water on the insects upon aquatic plants, so that they may fall and become its prey. Why is the jaculator fish of Java, so called P Because it kills insects and other prey, by ejecting, from its tubular mouth, single drops of water. Thus, when it spies a fly sitting on the plants that grow in shallow water, it swims 4, 5, or 6 feet from them, and then takes aim as above, when it rarely fails to strike the fly into the sea, where it soon becomes its prey. Why is a certain fisli of Ceylon called the leaf-moonP Because its outline has the appearance of a broad crescent, in the centre of which, the tail, short and fan- shaped, projects like a leaf. Why is a river better for fishing, after a flood from rain P Because it brings the fish up, who know when rain is coming ; and likewise brings down food, and makes the fish feed. But when the water is raised by a strong wind, the fish never run, as they are sure to find no increase in the spring-heads, which are their objects in running. Sir H. Davy. Why do experienced anglers fish with their face to- wards the sunP Because, though inconvenienced by the light, they do not then alarm the fish ; whereas, if they fished with their backs to the sun, and it was not very high, their own shadows, and those of their rods, would be thrown upon the water, and the fish would be alarmed whenever a fly was thrown. 200 KNOWLEDGE FOR THE PEOPLE. Thus, Cotton wishes for A day, with not too bright a beam ; A. warm, but not a scorching, sun. Why do fish not willingly haunt very deep water P Because, even in summer, it is of very low tempera- ture, approaching to 40, and it contains little or no vegetable food or insects, which the smaller fishes search for ; and the larger fishes follow the smaller. We cannot judge of the senses of animals which breathe water which separate air from water by their gills ; but it seems probable, that as the quality of the water is connected with their life and health, they must be exquisitely sensible to changes in water, and must have similar relations to it, that an animal with the most delicate nasal organs has to air. Sir H. Davy. Why does a fiood, or a rough wind, assist the fly- fisher P Because it not only obscures the vision of the fish, but, in a river much fished, changes the appearance of their haunts ; large trouts almost always occupy parti- cular stations, under, or close to, a large stone or tree ; and, probably, most of their recollected sensations are connected with this dwelling. Sir H. Davy. Why is it evident that the inferior animals have a knowledge of time? Because those which leave a particular dwelling at stated intervals, measure the distance they ought to travel, and return with regularity to their home. The sun appears to be their great regulator, as they are in- fluenced by the changes which take place with his light and heat. Fishes, and other animals, which live in the sea, or search for food on its shores, appear to regulate themselves by the motions of the tide. The regularity of the crowing of the cock, has been long admired ; but it appears difficult to point out the mea- sure of time by which it is governed.* Fleming. * See ORIGINS and ANTIQUITIES, Part III. p. 38. ZOOLOGY WORMS. 201 WORMS* GENERAL ECONOMY. Why are certain animals called invcrtebral P Because they are destitute of skull and vertebral column, for the protection of the brain and the spinal marrow. Why are these animals furnished with crusts, scales, or hairs P Because these appendices may supply the place of bones, and serve as a protection to the viscera, and as supports to the muscles. The blood, in those cases where a circulating fluid can be detected, is usually of a white or grey colour, seldom inclining to red. Why are certain of these animals called mollusca P Because they are soft, (from molluscus, Latin) and have no skeleton. Their muscles are attached to their skin, and their nervous system is irregular in its form and distribution. Why are others called annulosa P Because they have the body divided into joints or rings, (from annulus, a ring) and, they either possess articulated feet or have certain processes which supply their place. Why are some mollusca enabled to creep P Because they alternately contract and relax the foot, or expand their muscles, which serve as suckers, and make their motion analogous to that of serpents. Why do others swim P Because they make serpentine undulations of the foot and body, or exert tentacula, or expanded portions of the integuments. Many species rise or sink in the water by aid of an organ somewhat resembling the * Arranged in Six Orders : 1. Intestina 2. Mollus 'a 3. Testacea 4. Crustacea 5. CoraHia 6. Zoopliyta. 202 KNOWLEDGE FOR THE PEOPLE. air-bladders of fishes. Others keep, or shift their posi- tion by a sudden jerk, produced by shifting the valves of the shell rapidly. The common scallop and the river mussel have the latter properties. Why have some of these animals extraordinary power of suction P Because they may fix themselves more securely ; the sucker acting in the same manner as the moistened circular piece of leather, with a cord fixed to its centre, and applied to the surface of a stone. In the limpet, its surface is smooth and uniform ; and the adhesion appears to depend on its close application to every part of the opposing surface. In other animals, as the leech and sea-urchin, the sucker is formed at the ex- tremity of a tube ; the muscular motions of which may serve to pump out any air which may remain, after the organ has been applied to the surface of the body. In a third class, the sucker is more complicated in its structure, consisting of many smaller ones, so disposed as to act in concert, as on the breast of the lump-fish. Neither quadrupeds nor birds possess any sucker. It is found among a few reptiles and fishes. The extre- mities of the toes of many insects possess complicated suckers. Among the mollusca and zoophytes, there are few in which suckers in some form do not exist. By means of this organ, whose power of cohesion must depend, not only on the extent of its surface, but the strength of the muscles which produce the vacuum, these animals can remain in the same spot, although acted on by forces to which their own weight could offer no adequate resistance. Pennant states that he heard of a lamprey, which was taken out of the Esk, weighing three pounds, adhering to a stone of twelve pounds weight suspended at its mouth. Fleming. Why are zoophytes considered the lowest family of animals P Because they have not a heart or system of vessels. ZOOLOGY WORMS. 203 THE EARTH-WORM. Why is the earth-worm so called ? Because it swallows the soil or earth, from which, in its passage through the intestines, it extracts its nourishment.* Mr. Leon Dufour has recently deter- mined the earth-worm to be an oviparous and not a viviparous animal. The eggs resemble a chrysalis or a cocoon, but their pulp, &o. prove them to be true eggs. The lower we go in the scale of creation, the more surprising is the reproductive faculty. The gardener cuts the earth-worm with his spade ; but the injury, far from diminishing animal life, increases it; for each portion of the animal so divided, becomes a separate creature, having a system of parts speedily regenerated. THE LEECH. Why does the leech advance faster than other worms? Because the organs of adhesion are double, one at each extremity, the mouth adhering to one part of the surface, while the tail is brought up towards it, and is fixed, the body being at this time like an arch. The head then quits its hold, the body extends itself, and, and when at full length the head is then attached, and the tail brought up. By these alternate movements, the leech, at every step, advances nearly the length of its own body. Fleming. The stomach occupies the greatest part of the body in the leech, and is divided internally, by means of ten imperfect fleshy partitions, into somewhat separate portions. * In a recent paper in the Foreign Quarterly Review we read of other earth-eaters, in South America, where the women, children, serpents, lizards, and ounces of the river St. Francisco have a singular and most economical propensity of eating earth. It seems that the soil contains a small portion of salt-petre, which is agreeable to the palate. Boys and girls, however, are less select in their tastes, and sometimes eat the whitewash off the walls, and occasionally, wood, charcoal, or cloth. 204 KNOWLEDGE FOR THE PEOPLE. Why is the wound of the leech of three-sided form? Because within its mouth are three semicircular projected bodies, with a sharp toothed edge, with which it bites. Why is a certain species called the flying leech P Because it has the power of springing-, by means ot a filament, to a considerable distance. It is much smaller than the common leech ; the largest, when at rest, not being more than half an inch long, and may be extended till it becomes a fine string ; the smaller ones are very minute. It is common in the jungles in Ceylon; Bishop Heber tells us that " the native troops on their march to Canely, suffered very severely from the bites of flying leeches, occasionally even to the loss of life or limb : their legs were covered with them, and streamed with blood." SNAILS. Why do snails carry their shells with so much ease P Because they are bound to the shells by two mus- cles, which arise from the pillar, and having pe- netrated the body below its spiral part, run forward under the stomach, and spread their fibres in several slips, which interlace with those of the muscles proper to the foot, the substance of which they enter. It is obvious from this direction, that on their contraction, the body of the snail must be drawn within the shell. When it wishes to re-issue, the head and foot are forced out by circular fibres, which surround the body immediately above the foot. Cuvier. Blumenbach says "Whether the black points, at the extremities of what are called the horns of the common snail, are organs which really possess the power of vision, is still problematical." Compar. Anat. Why does the snail mark its track ivith a silver line of concrete slime P Because the slime enables the slug to attach one part of its body more firmly to the surface on which ZOOLOGY WORMS. 205 it is moving, while it drags up the remainder to anew position. In England the rustic maiden once read her fortune in the meanders of a snail : Last May-day fair I search'd to find a snail, That might my lover's name reveal ; She placed it on " the milk-white embers spread," when Slow crawl'd the snail ; and, if I right can spell, In the soft ashes mark'd a curious L. Oh ! may this wondrous omen lucky prove, For L: is found in Lubberkin and love. Gay. Why are snail-shells so often found adhering to rocks, $*c.P Because the snails have then retired to torpidity, previous to which they have formed an operculum or lid from the mouth of the shell, by which they attach themselves, and at the same time close up even all access of the air. The winter lid of some snails re- sembles a piece of card paper. All the land testacea (shell animals) appear to have the power of becoming torpid at pleasure, and inde- pendent of any alterations of temperature. Thus, snails, if placed in a box at midsummer, will attach themselves to its sides, and remain in this dormant state for several years. Even in their natural haunts, they are often found in this state during the summer season, when there is a continued drought. With the first shower, however, they recover, and move about, and at this time the conchologist ought to be on the alert. Why do snail-shells become more brilliant when plunged into boiling water p Because the skin or film with which they are co- vered, is then removed. Why have some snail-shells elevated ribs, and others slight depressions P Because the shell is gradually formed by the snail, by aid of a fold or membrane, to be perceived where the body rises into the shell. This part is denominated 20(3 KNOWLEDGE FOR THE PEOPLE, the collar, from the manner in which it surrounds the body, and it is the organ which secretes the shell. The animal is horn with the rudiments of its future cover- ing, and by its gradual increase of growth is enabled to push the collar for a space, and from time to time beyond the original margin. In these operations, a thin layer of membraneous and calcareous matter is excreted and deposited, which is gradually thickened by successive layers being laid on within the first, by the repeated protrusions and retractions of the collar. This portion being formed, the animal commences another, and finishes it in the same manner ; and the extent of each portion is marked as above. There is not, as has been implied, a regular and alternate de- position of a layer of membrane, and a layer of lime ; but, in all shells, the animal and earthy matters are obviously secreted and deposited at the same moment, and in commixture. Why is the snail found in greater numbers, and thriv- ing better, in chalky districts than elsewhere P Because chalk is the snail's best food, and the food is the source of the lime of which it forms its shell. Lime is not, however, necessary to be eaten for the perfect formation of the operculum, (or lid of the shell) as is remarked in the Zoological Journal by Mr. Bell; many snails in his possession having formed that part, though during the whole summer they had no access to any preparation of lime. Why do the land snails vary most in their colours P Because they are most exposed to the operation of light ; while those shells, which, within the bodies of their snails are always white, as are also those which live in holes whence they never issue. Another striking proof of the blanching effect of darkness is furnished by some bivalve shells, as scallops, permanently affixed by their lower valve, which inconstantly white, while the upper one may possibly be variegated with bright colours. ZOOLOGY WORMS. 207 Why u'cts a certain species of snail reared with much pains among the Romans P Because they were eaten as great delicacies among epicures. For this purpose, they were kept in sties, and fattened with bran and sodden wine ; and on this generous fare they grew occasionally to such a size, that, according to Varro, the shell would hold full ten quarts ! The younger Pliny's supper of three snails, two eggs, a barley cake, a lettuce, sweet wine, and snow, was therefore no very spare meal. Snails are still eaten in great numbers on the con- tinent of Europe, particularly in Lent. In Switzerland they are fed in many thousands together in gardens ; in Italy they are much liked ; in Paris they are sold in the market ; and, in Vienna, they are charged at an inn the same as a plate of veal or beef, or a dish of frogs at a French restaurateur*. The Greeks are also great eaters of land-snails, but they have not the art of fattening them. The usual mode of preparing them for the table is either boiling, frying them in butter, or stuffing them with force-meat. Why were edible snails introduced into England about the middle of the sixteenth century P Because of their being recommended for consump- tive complaints by the physicians of that day ; indeed, snail-water is still to be found in the pharmacopoeia of the last century. Snails were introduced as above by Charles Howard, one of the earls of Arundel, who brought them from Italy for the cure of his countess. Sir Kenelm Digby likewise patronized the remedy. Elias Ashmole says, the earl scattered them on the hills about Dorking, in Surrey, and between Albury and Horsley, near Guild- * There is in Brussels a market for frogs, which are brought alive in pails and cans, and prepared for dressing on the spot. The hind limbs, which are the only parts used, are cut from the body with scis- sors, by the women who bring- the animals for sale. 208 KNOWLEDGE FOR THE PEOPLE. ford. We Lave noticed, in our Promenade round Dork- ing, their being on Box Hill, where to this day large snails abound. They were also introduced a few years since into a curious garden in Scotland, where they did not prosper. Why is the Cornwall mutton of superior flavour P Because of the nourishment afforded to the sheep by feeding on snails. Thus, the sweetest mutton is reckoned to be that of the smallest sheep, where the sands are scarcely covered with very short grass. " From these sands come forth snails of the turbinated or spiral kind, which spread themselves over the plains early in the morning, and whilst they are in quest of their own food among the dews, yield a most fattening nourishment to the sheep." Borlase's Hist. Cornwall. Why are snails eagerly sought by the blackbird and the thrush P Because they are substituted for their summer food, which winter may have destroyed. They break the shells of the snails, by reiterated strokes against some stone ; and it is not uncommon to lind a great quan- tity of fragments of shells together, as if brought to one particular stone for this very purpose. THE MAN-OF-WAR. Why is a certain worm called the man-of-war P Because it has the skill and knowledge of an expe- rienced navigator, and is in itself a little ship. Its evolutions are according to the winds ; it raises and lowers its sail, which is a membrane provided with elevating and depressing organs. When filled with air, it is so light, that it swims on the surface of alco- hol, and is at the same time provided with a structure which furnishes it with the necessary ballast* In high winds it descends into the deep. From the underside of the body proceed tubes, 20 v feet in length, which wind in a spiral form like a screw, serving at once as anchors, defensive and offensive weapons, air- tubes, ZOOLOGY WORMS. 209 and feelers. It has tlie colours of the rainbow ; its erest or sail is intersected with pink and blue veins ; its length is from six to eight inches. The fibres con- tain a poisonous fluid, which stings like nettles. We abridge these curious facts from a Memoir of Dr. Ti- lesius, who accompanied Krusenstern in his voyage round the world. CUTTLE-FISH. Why docs the cuttle-fish differ in structure from other mollusca ? Because it has three hearts two of which are placed at the root of the two branchiae ; they receive the blood from the body, and propel it into the branchiae. The returning veins open into the middle heart, from which the aorta proceeds. Cuvier. The cuttle-fish was esteemed a delicacy by the an- cients. Captain Cook also speaks highly of a soup he made from it ; and the fish is eaten at the present day by the Italians, and by the Greeks, during Lent. Why does the cuttle-fish, when pursued, eject a Hack inky liquor? Because it may darken the water, and thus hide itself from its enemies. It is a completely mistaken notion, that the black fluid of the cuttle-fish is its bile ; for the ink-bag is at a considerable distance from the gall-bladder. Ac- cording to Cuvier, the Indian Ink, which comes from China, is made of the above fluid. Why are the jaws of the cuttle-fish fixed in the flesh of the animal? Because there is no head to which they can be arti- culated. They are of horny substance, and resemble exactly the bill of a parrot. They are in the centre of the lower part of the body, surrounded by the tentacula. By means of these parts, the shell-fish which are taken for food, are completely triturated. 210 KNOWLEDGE FOR THE PEOPLE. Why have cuttle-fish small holes on their arms P Because, by means of them, they fix themselves in the manner of cupping-glasses. These holes increase with the age of the animal ; and, in some species, amount to upwards of 1,000. They have the power of repro- ducing their arms, which are often torn or nipped off by shell and other fishes. The suckers of the cuttle-fish, are irregularly scat- tered on the arms and feet. The back is strengthened by a complicated calcareous plate, lodged in a peculiar cavity. This plate has long been known in the shop of the apothecary, under the name Cuttle-fish bone, which was formerly prized as an absorbent, but is now chiefly sought after for the purpose of polishing the softer me- tals. Fleming. Why is it improper to call this plate " bone " ? Because, in composition, it is exactly similar to shell, and consists of various membranes, hardened by car- bonate of lime, without the smallest mixture of phos- phate. Hatchett, in Phllos. Trans. The most remarkable species of cuttle-fish inhabits the British seas ; and, although seldom taken, its bone is cast ashore on different parts of the coasts, from the south of England, to the Zetland Isles. We have picked up scores of these bones, or shells, on the Sus- sex coast, but never found a single fish. The cuttle-fish, it may be added, is the only animal of its class, in which any thing has hitherto been dis- covered, at all like an organ of hearing, or has been shown to possess true eyes. Why are sea-grapes, as they are called, often picked up on the sea-shore P Because many kinds are the ovaria, (or egg-bags) of cuttle-fish, and similar species. Why are certain sea-worms called animal flowers P Because they display beautiful membraneous expan- sions, resembling the petals of flowers : these are, in ZOOLOGY TESTACEA. 211 fact, the breathing organs, acting at the same time as tentacula. Why does the stomach of some medusa resemble the roots of trees P Because it has branching tentacula, on which canals commence by open orifices; these unite together to form larger tubes ; and the successive union of these vessels, forms at last four trunks, which open into the stomach, and convey the food into that cavity. Cuvier has formed a new genus, under an appellation derived from the above comparison the rhizostoma; from the Greek words, a root and a mouth. TESTACEA SHELLS. Why is the study of shells much more important than some would represent? Because, being found in abundance, in a great variety of rocks and positions, they constitute the medals of the ancient ivorld ; and, from an accurate acquaintance with their different species, and with the nature of the animals that represented them, many curious and important deductions respecting the form- ation and changes of the crust of the earth may be drawn. Thomson's Hist. Royal Soc. Testacea, (or shell animals) are classed in families, according to the number and form of the shells. Thus multivalve, or with many valves ; bivalve, muscles, &c. ; univalve, with regular windings, snails ; and univalves, without such windings. Why have shells served many purposes more useful than that of ornament P Because of their service in the domestic economy of various nations. Thus, in the south of China and in India, the thin layers of some large flat shells, when polished, are used instead of glass for windows. Many of the domestic utensils of savage people are shells ; and it must have been observed, that we frequently 212 KNOWLEDGE FOR THE PEOPLE. imitate these in our porcelain. In India, drinking- cups are formed of the nautilus; and in other less civi- lized nations, shells are converted into knives, spoons, fishing-hooks, razors, &c. In Zetland, a certain shell, suspended horizontally by a cord, is used as a lamp, the canal serving to hold the wick, and the cavity to contain the oil. Is it not probable that some of the most elegant patterns left us by the Greeks have been suggested by a similar primitive practice ? In mentioning the benefits of shells, we must not forget the celebrated Tyrian purple, which was pro- cured from a univalve shell fish, and was contained in a transparent and branching vessel, placed behind the neck of the animal. A shell, called Purpura, of our own shores, furnishes a liquid of similar qualities, and is supposed to have been resorted to by the ancients. Why was the term " shell " formerly expressive of the greatest hospitality P Because, in the days when Ossian sang, the hollow shells of the scallop were the drinking-cups of Fingal and his heroes, and the flat shells their plates. Thus, in Ossian : " Thou, too, hast often accompanied my voice in Branno's hall of shells." " The joy of the shell went round, and the aged hero gave the fair." Why do shells increase in size? Because they consist of layers of an earthy salt, with interposed membranes of animal matter, resem- bling coagulated albumen, and they grow, by the addi- tion of layers of new matter, to the edges and internal surface. When broken, the animal can cement the edges, and fill up the crack, or supply the deficiency when a portion is abstracted. Fleming. As an instance of the great strength of such cement, it was, in 1829, stated in Branded Journal, that the large snails which are found in gardens and woods, discharge a whitish substance, with a slimy and gela- tinous appearance, which has been known to cement ZOOLOGY TESTACEA. 213 two pieces of flint so strongly, as to bear dashing on a pavement without the junction being disturbed, al- though the flint broke into fragments by fresh fractures. Why are shells of different colours P Because the colour is secreted by the animal, along with the matter of the shell. Why is the inner surface of all shells very smooth, and apparently denser and harder than the outer P Because the animals, to form this inner layer, ex- crete the lime in nearly a pure state, that is to say, mixed with much less animal matter ; so that, in con- creting, the particles become very close and compact, and receive a polish from the repeated frictions of the soft parts. Why does a dry thin skin cover the external surface of most shells P Because, being a dried sheet of coagulated albumen effused at the same time, or, perhaps, even prior to the first layer, it may protect the subjacent or more chalky layers from the action of the air or water during their consolidation. Mr. Gray, in the Zoological Journ. Blainville, and the French naturalists, generally, suppose that the above covering is the true epidermis, or scurf-skin, raised from its position by the deposition of the shell underneath it ; but we think this is not tenable. Why are old shells remarkably strong P Because a shell having attained its full growth, the changes which the animal further effects are almost limited to some increase of its thickness ; not, however, by the addition of any new layers, but by the effusion of vitreous matter. Hence, holes and canals, previ- ously visible, are now filled up ; the aperture con- tracted, and the margins strengthened arid enlarged ; the upper part of the spire, perhaps, filled and made more solid. The external layers now lose their epi- dermis; the colours become paler; parasites deform 214 KNOWLEDGE FOR THE PEOPLE. and perforate the outer surface ; death at length over- takes the architect, and the shell decays under the in- fluences of the water and the air. What an epitome is this of the proudest life, till death Comes at the last, and with a little pin Bores through his castle-wall, and farewell king. THE PIERCE-STONE. Why is a certain worm called the pier ce-stone P Because it bores passages in rocks, even in the hardest marble, in the stems of coral, oyster-shells, the bottoms of ships, &c. and excavates a habitation at the termination of the passage. Blumenbach. The Lithophagus is another of these stone-boring animals, and an instance of its depredations on the hardest marble is shown by the celebrated, but mys- terious, phenomenon, of the three large columns of Cippolino antico, in the temple of Serapis, at Pozzuolo, which, though at an elevation of twenty-seven feet above the level of the Mediterranean near them, are perforated in a circular manner by these animals. THE OYSTER. Why is the shell of the oyster termed "fixed"? Because it has one valve cemented to the rock ; and though the oyster itself has a heart, blood-vessels, brain, gills, and stomach, it depends on the bounty of the waves for all the objects of its sensation and nou- rishment. It is, however, an admirable provision of na- ture, that although the oyster and othei natives of the water are thus stationary themselves, the fluctuations of the element in which they live, produce a variety in the scene, and daily bring new objects in contact with their organs of sensation. Of oysters there are several species. Thus, in a little Manuel de V Amateur d'Huitres, before us, we count upwards of forty-five Afferent kinds which are known to naturalists. Why does an oyster open its shell at the time of flood ? ZOOLOGY. TESTACEA. 215 Because it may participate and enjoy the returning tide. This is done, as well as the shell closed, with prodigious force, by means of a strong muscle at the hinge. Mr. Carew, in his Survey of Cornwall, 1602, tells us of an oyster having opened its shell, and three mice attempting to seize it ; but the oyster clasped fast its shell, and killed them all. THE MUSSEL. Why is the common mussel enveloped in a thread-like substance termed byssus ? Because these threads are united in the body to a secreting gland, furnished with powerful muscles, and, at the other extremity, glued to the rock or other body to which it connects itself. Fleming. Why are the pinnae , or sea-wings prized ? Because of their beard, by means of which they attach themselves, and from which gloves, &c. are manufactured at Smyrna, Tarentum, Palermo, &c. A pair of gloves made of this material may be seen in the British Museum. Why are pearls found in the oyster P Because they consist of the morbid secretions of the fish, situated either in the body, or lying loose between, it and shell ; or, lastly, fixed to the latter by a kind of neck. It is said they do not appear until the animal has reached its fourth year. There is nothing pecu- liar in their chemical composition, being merely car- bonate of lime. The Romans gave almost incredible prices for pearls. Their finest pearls were from the Gulf of Persia, and the Indian Ocean ; though it is matter of history that Caesar was induced to invade Britain from some exaggerated accounts he had heard of the pearls of our coasts, or rather of our rivers ; but, if 216 KNOWLEDGE FOR THE PEOPLE. these were his objects, the mercenary conqueror was disappointed, for they were found to he of had colour and inferior size, nor have they since improved. Why did Linnceus owe his patent of nobility to the pearl P Because he received that elevation for a discovery of causing the fresh-water mussels of Sweden to pro- duce pearls at his pleasure. It is conjectured that he accomplished this by drilling small holes through the shells ; hut his method is not certainly known. THE NAUTILUS. Why is the Paper Nautilus also called the Argonaut P Because of its origin from ArgonauteS) the com- panions of Jason, in the celebrated Ship Argo, and from the Latin naus, a ship ; the shells of all the Nautili, having the appearance of a ship with a very high poop. When sailing, the animal expands two of its arms on high, and between these supports a mem- brane which serves as a sail, hanging the two other arms out of its shell, to serve as oars, the office of steerage being generally served by the tail. When the sea is calm, whole fleets of these Nautili may be seen diverting themselves ; bat when a storm arises, or they are disturbed, they draw in their legs, take in as much water as makes them specifically heavier, than that in which they float, and then sink to the bottom. When they rise again, they void this water by numerous holes, of which their legs are full. The cuttle-fish, from its frequently being found in the shell of the Argonauta, was long considered the fabrication of the shell ; but, more recent observation has proved it to be merely the piratical occupant. END OF PART VIII. t,oM)ON: Printed by C.Rlcharda, St. Mar tin" s -Inn t\ ( h tiring -cross* ZOOLOGY. INSECTS. GENERAL ECONOMY. WHY are insects so called? Because they have a separation in the middle of their bodies, whereby they are cut (insectus, cut or notched, Lat.) into two parts, joined by a small liga- ture, as in the common house-fly. Why are the history and descriptions of insects called Entomology P Because of the origin of that term from the two Greek words, entoma, insects ; and logos, a discourse. Why is the study of insects a source of perpetual va- riety P Because the localities of insects are, to a certain ex- tent, constantly changing. Insects, also, which are plentiful one year, frequently become scarce, or dis- appear altogether the next a fact, strikingly illus- trated by the uncommon abundance in 1826 and 1827, of the seven-spot lady-bird in the vicinity of London, though during the two preceding summers, this insect was comparatively scarce, while the small two-spot lady-bird was plentiful. /. Rennie. Why did the ancient philosophers believe that mag- gots, flies, and other insects, were generated from putri- fying substances P Because they were found about animal bodies in a state of decomposition ; and the circumstance was merely noticed without any previous or accurate observation of the means by which they were first produced. The B2 220 KNOWLEDGE FOR THE PEOPLE. fact is now established, that all insects come from eggs, as plants do from seeds. Why is the life of insects the briefest of all exist- ence? Because the males rarely survive the inclemency of the first winter, and the females die after having de- posited their eggs. Why may the ephemeral nature of many tribes of in- sects be considered rather apparent than real P Because the wonderful metamorphoses to which they are subjected, conceal their identity from the eye of the uninitiated, and greatly interfere with a conti- nuous tracing of the same individual, from the egg to the perfect form. For example many aquatic flies, such as the Ephemerae and others, whose declared and more obvious existence, does not exceed a few hours, have, previous to their assuming the winged state, spent months or even years in the banks of rivers, and beneath the surface of the stream. Why is the Linn&an arrangement of insects considered superior to others. Because the primary divisions of Linnaeus are taken from circumstances connected with the condi- tion of the wings. The simplicity of this method, and the obviousness of the characters which have been em- ployed, have secured for this system a decided prefer- ence among the entomologists of Britain. Fleminy. Why is the first Linnccan order of insects called Coleoptera P Because they have wings in sheaths: (koleos, a sheath pteron, a wing ;) as the common black-beetle : 4,087 species. Why is the second order called Hetniptera P Because they have half of one \\ing overlaid by the other : (hemisu, half pteron^ a wing ;) as the common cockroach : 1 ,427 species. Why is the third order called Lepidoptera P ZOOLOGY. INSECTS. 221 Because they have wings covered with very fine scales : (lepis, a scale pteron, a wing ;) as the butter- fly : 2,570 species. Why is the fourth order called Neuroptera ? Because they have reticulated or nerved wings: (neuron, a nerve ptcron, a wing ;) as the dragon-fly : 174 species. Why is the fifth called HymcnopteraP Because they have membraneous wings : (hymen, a film pteron, a wing ;) as the bee : 1,265 species. Why is the sixth order called Diptera P Because they are two-winged : (dis, twice pteron, a wing ;) as the common gnat : 692 species. Why is the seventh order called Aptura P Because they have no wings : (a, privative pteron, a wing ;) as the spider and the centipede : 679 spe- cies. About thirty years ago, the recorded number of in- sects amounted to about eleven thousand ; but a great additional number has since been discovered and de- scribed: Humboldt says 44,000. Why is it evident that the nourishment in insects is not merely calculated for the preservation of the indi- vidual^ but more particularly for the purpose of con- suming organized matter ** Because insects must eat, not solely to satisfy hunger, but also to destroy carrion, to annihilate other insects, to extirpate weeds, &c. ; an admirable provi- sion, to the execution of which, besides the almost in- calculable number of species, the extremely rapid multiplication of many, the unexampled voracity of others, and the quickness with which digestion is car- ried on in their very short intestinal canal, all tend to contribute. Thus, it is known, that a caterpillar will, in twenty-four hours, consume more than three times its own weight. Blumenbach. B3 222 KNOWLEDGE FOR THE PEOPLE. Why may the abode of insects on and under the sur- face of the earth, be considered as much less limited than that of the other classes of animals P Because they are found on almost all warm-blooded animals ; and even the larger insects, as bees, chaffers, c. are infested by peculiar kinds of lice. There are but few plants, also, (such as, perhaps, the yew, savine, and most tree-mosses,) which do not serve for the abode and support of known insects. Many again, as the oak, are frequented and inhabited by more than a hundred distinct species. Generally, however, as insects are diffused over the earth, the residence of individual species is not less frequently limited to a very small number of animals and plants, or even par- ticular parts of them. Why are insects so serviceable in the general economy of nature P Because some destroy numerous kinds of weeds in the bud, or extirpate them when full grown. Others feed on carrion, live in dung. &c., and thus destroy, disperse, and change noxious animal substances ; on the one hand, obviating the infection of the air ; and on the other, promoting the fertilization of the earth. It is in this way, for instance, that flies are so serviceable in warm climates. So again, innumerable insects effect the impregnation of plants in a very remarkable manner. Why are insects important in the artsP Because of the ready adaptation of their labours to many of the conveniences of life. Thus, mead is pre- pared in many parts of Europe from the honey of bees ; silk is employed for clothing : several insects, as co- chineal, afford excellent dyes. Galls are employed for ink ; wax, for lights, and other purposes. Lac, employed to make varnish, sealing-wax, c. is pro- duced by a certain Indian species of coccus. As me- dicines, we have Spanish flies, ants ; and, adds Blu- ZOOLOGY.' INSECTS. 223 meubach, the oil-beetle, recommended for hydropho- bia, and many beetles for relieving tooth-ache. Why are the eyes of certain insects termed compound? Because they consist of an aggregation of smaller eyes, or those which are termed simple; for their gene- ral convexity is divided into one immense number of small hexagonal or six-sided convex surfaces, which may be considered cornea. Simple eyes are formed in the larvae of many winged insects, which upon their last or complete metamorphosis, at the same time that they receive their wings, gain the large compound eyes. The late Mr. T. Carpenter, the optician, of Re- gent-street, paid more attention to this branch of en- tomology than any man of his time. By aid of a powerful microscope, he experimented upon upwards of 200 insects ; the most familiar of which were the boat-fly, dragon-fly, ant, gnat, bee, wasp, ichneumon, cockchaffer, peach-fly, earwig, grasshopper, locust, cricket, and cockroach. His results were a conviction that the whole of these insects did really possess nu- merous and distinct eyes, varying in number according to the species of insect ; in some, upwards of 40 in others, 1 ,000 ; and upwards of 30,000 in some species ! The eyes of the libellula, or dragon-fly, Mr. Carpenter says, are, on account of their size, peculiarly well adapted for examination under the microscope. They are a couple of protuberances immoveably fixed in the head, and divided into a number of hexagonal cells, each of which contains a complete eye. The external parts of these eyes are so perfectly smooth, and so well polished, that when viewed as opaque objects, they will, like so many mirrors, reflect the images of all surrounding objects: each of these protuberances, in its natural state, is a body cut into a number of facets, like an artificial multiplying glass but with this su- periority in the workmanship, that as in that glass every facet is plane, here every one is convex ; they are also much more numerous, and contained in a much 224 KNOWLEDGE FOR THE PEOPLE. smaller space. Each of the eyes is an hexagon, vary- ing in size, according to its situation in the head ; and each of them is a distinct convex lens, and has a simi- lar effect of forming the image of an object placed be- fore it. Blumenbach observes, compound eyes seem calcu- lated for seeing at a distance ; simple eyes, for looking at near objects ; at least it may be supposed so, as we find that butterflies, in their perfect winged state, have such large compound, telescopic eyes ; whilst, as cater- pillars, they have small simple ones. Only a few in- serts can move their eyes, and from this fact has been deduced a probable explanation of at least one object of the numerous facets or surfaces of which the com- pound eyes of insects are composed. Leuwenhoeck has counted 17,235 facets in the cor- nea of a butterfly. Why have insects antennae or feelers P Because the organ of touch is not generally distri- buted over the body, and the antennae are considered as appropriated to this sense. These organs are two or more in number, and are present in all the Crustacea and insects, but wanting in the arachnidae, or spider genus. They are situated on the head, usually be- tween the eyes and the mouth. They consist of a num- ber of joints, in general capable, by their flexibility, of examining the surface of a body. Fleming. Why are these antenna particularly necessary to in- sects P Because of the insensibility of their outward coat, which is generally of a horny consistence ; and also from their eyes being destitute, in most instances, of the power of motion. The feelers of insects are better adapted for explor- ing the condition of the surfaces of bodies than any organ which we possess. But their sensibility of touch is limited to particular qualities^ or confined within ZOOLOGY. INSECTS. 225 narrow bounds. The human hand, on the contrary, by its motions, the pliability and strength of the fin- gers, and the softness of the surface, is the most ex- tensive and perfect organ of touch possessed by any animal . Fleming . Wliy have insects cushions on the under surface of their joints P Because these cushions being either soft and smooth on the surface, or enlargements closely covered with short hairs, by their elasticity and resistance, aid the animal in climbing and leaping. They have likewise suckers, which, in all, are capable of being applied to the surface of a smooth body. By these means those insects which walk upon walls and trees, are enabled to overcome the resistance of gravitation. Why does the mouth of Crustacea and some insects differ from that of red-blooded animals P Because it is formed of two or more jaws placed laterally ; these move from without inwards, and, vice versa, whereas those of red-blooded animals move from above downwards, and back again. The parts which are termed the lips of insects, are two bodies ; one of which is placed above or in front of the jaws, and the other below or behind them. The palpi (or short an- tennae) are articulated to the jaws. Notes to Blumen- bach's Comp. Anat. Why have all insects with jaws the power of masticat- ing hard animal and vegetable substances P Because these parts are of a firm, horny texture, and in many cases are very large, when compared with the size of the animal. The locust, the dragon-fly, the beetle, especially the stag-beetle, are examples in which the edges are very large and manifest, and often pos- sess tooth-like edges. Why does the sting of insects not only pierce the skin, but leave considerable pain? Because the sting is hollow, and conveys the irritat- 226 KNOWLEDGE FOR THE PEOPLE. ing or poisonous fluid within the wound, from a pecu- liar bag. Why does the sting usually remain in the wound which it inflicts P Because it is barbed at the sides of its point. Why have insects without jaws long tubular tongues ? Because they derive their nourishment chiefly from liquids, which they get from animal or vegetable sub- stances by means of this spiral or tubular tongue, or a soft proboscis with a broad opening, admitting of ex- tension and retraction ; or a horny pointed tube, con- taining sharp bristly bodies internally. In many species of the butterfly, this proboscis, when not in use, is coiled up like a watch-spring. Why are insects supposed to possess the organs of hearing, although no traces of such organs have been de- tected in them P Because they emit a variety of sounds by the fric- tion produced by their mandibles, their wings, and their legs, which are communicated to others, and un- derstood by them. The proofs of the existence of taste and smell in the different tribes, rest on the same foundation, the evidence of the function being per- formed. These senses are chiefly used in the animal economy in subserviency to the digestive system. The organs in which they reside are probably the palpi (re- sembling short antennae) or the other more flexible parts of the mouth. But these parts are so different in their form from the organs employed for the same purpose in the higher classes of animals, and so dimi- nutive in size, that neither analogy nor dissection can be called in to illustrate the subject. Fleming. Numerous facts have long ago proved that several insects can distinguish the odorous properties of bodies even at considerable distances. But the organ in which that sense resides has -siot been clearly pointed out. From the German. ZOOLOGY. INSECTS. 227 Why is the alleged cruelty of entomological pursuits but a futile objection to the practical studies of natural history ? Because cruelty is an unnecessary infliction of suf- ering, when a person is fond of torturing or destroying God's creatures from mere wantonness, with no useful end in view ; or when, if their death be useful and lawful, he has recourse to circuitous modes of killing them, where direct ones would answer equally well. In utility, the sportsman, from his primary object being amusement, must yield to the entomologist, who adds to the general stock of mental food, often sup- plies hints for useful improvement in the arts and sciences, and the objects of whose pursuits, unlike that of the sportsman, are preserved, and may be applied to use for many years. Again : in proportion as we descend in the scale of being, the sensibility of objects that constitute it diminishes. The earth-worm, so far from being injured by cutting, thereby acquires an extension of existence.* Insensibility almost equally great may be found in the insect world. This might, indeed, be inferred a priori, since, Providence seems to have been more prodigal of insect life than of that of any other order of creatures, animalculae perhaps alone excepted. We abridge the spirit of this inge- nious defence from the valuable Introduction to En- tomology, by Kirby and Spence, who illustrate the position by observing, " It is not easy, in some parts of the year, to set foot on the ground without crushing these minute animals. * * * Can it be believed that the beneficent Creator, whose tender mercies are over all his works, would expose these helpless beings to such innumerable enemies and injuries, were they endued with the same sense of pain and irritability of nerve with the higher orders of animals?" Instead, there- * See EARTHWORM, page 203. 228 KNOWLEDGE FOR THE PEOPLE. fore, of believing and being grieved by the belief, that the insect we tread upon " In corporal sufferance finds a pang as great As when a giant dies," the very converse is nearer the truth. " Had a giant lost an arm or a leg," continue the authors just quoted, " or were a sword or spear run through his body, he would feel no great inclination for running about, dancing, or eating. Yet a tipula (crane-fly) will leave half its legs in the hands of an unlucky boy who has endeavoured to catch it, and will fly with as much agility and unconcern as if nothing had happened to it ; and an insect impaled on a pin will often devour its prey with as much avidity as when at liberty. Were a giant eviscerated, his body divided in the middle, or his head cut off, it would be all over with him ; he would move no more ; he would be dead to the calls of hunger, or the emotions of fear, anger or love. Not so our insects : I have seen the common cockchaffer walk about with apparent indifference after some bird had nearly emptied its body of its viscera ; a humble-bee will eat honey with greediness though deprived of its abdomen ; and I myself lately saw an ant, which had been brought out of the nest by its comrades, walk when deprived of its head. The head of a wasp will attempt to bite after it is separated from the rest of the body ; and the abdomen, under similar circumstances, if the finger be moved to it, will at- tempt to sting." Why do insects live, and (so far as we can perceive]) feel comparatively little pain from the loss of their limbs P Because, though possessed of nerves, they have nothing similar to our brain and spinal cord, the two sources of our nerves of feeling and of motion ; but, instead of this, they have a chain of ganglia, or bundles of nervous substance, and from each of these bundles, nerves branch out to the parts contiguous, ZOOLOGY. INSECTS. 229 each ganglion forming the centre of feeling to the parts to which its nerves run, or having its own set of nerves. Many curious particulars connected with the great tenacity of life in insects are mentioned by entomolo- gists, as well with a view to illustrate the animal eco- nomy, as to defend their favourite pursuit. Riboud stuck different beetles through with pins, and cut and lacerated others in the severest manner, without greatly accelerating death. Leuwenhoeck had a mite which lived eleven weeks transfixed on a point for microsco- pical observation. Vaillant caught a locust at the Cape of Good Hope, and after excavating the intes- tines, he filled the abdomen with cotton, and stuck a steel pin through the thorax, yet the feet and antennae were in full play after the lapse of five months. A decapitated beetle will advance over a table, and re- cognize a precipice on approaching the edge. Colonel Pringle decapitated several libellulae, or dragon-flies, one of which afterwards lived for four months, and another for six ; and, which seems rather odd, he could never keep alive those with their heads on above a few days. Mr. Ha worth, the well-known English entomo- logist, being in a garden with a friend who firmly be- lieved in the delicate susceptibility of insects, he struck down a large dragon-fly, and in doing so he unfortu- nately severed its long abdomen from the rest of its body. The mutilated insect after this devoured two small flies. Mr. Haworth then contrived to form a false abdomen, by means of a slender portion of a feranium ; after which the dragon-fly devoured another y, and, on being set at liberty, it flew away with as much apparent glee as if it had received no injury. It is well known to practical entomologists, that large moths found asleep during the daytime, may be pinned to the trunks of trees without their appearing to suffer such a degree of pain as even to awake them. It is only on the approach of the evening twilight that they 230 KNOWLEDGE FOR THE PEOPLE. seek to free themselves from what they must no doubt regard as an inconvenient situation.* Considerations such as those glanced at in the pre- ceding page can never, of course, be so misconstrued as to afford any palliation to wanton or inconsiderate cruelty to the brute creation. Why does the shin of insects differ from that of the vertebral animals ? Because, in insects, the skin serves the double pur- pose of protection and support, and represents the cutaneous and osseous system of the latter. Its struc- ture appears much more simple than in the higher classes, as it can neither be said to possess a mucous or cellular web or true skin. It bears the nearest re- semblance to the cuticle of the skin of the higher classes, or, rather, all the lamina? of perfect skins are here incorporated into one uniform plate. In some genera it is soft and pliable ; while, in others, as some of the weevils, it approaches the consistence of bones, or appears as a calcareous crust in the crabs. In some species it is elastic, in others brittle. (Fleming.) Again, the coat, composed of several portions, moving on one another like the pieces of a gauntlet, also serves to protect the insect from, the effects of various accidents. Why are not the spines and hairs of insects easily rubbed off? Because they are merely elongations of the skin. It is otherwise with scales. Some of these are inserted into the skin at one end and left free at the other, and in some insects are so feebly connected, as to fall off by touching them with the finger. These scales, in the butterfly, bear a remote resemblance to feathers in their form. Why do many insects leap? with ease ', forwards, bach- ivards, and laterally P * See Encyclop. Brit., art. Animal Kingdom, vol. iii.Tth edit. 1831. ZOOLOGY. INSECTS. 231 Because the thighs of their hind legs are of uncommon size, to give room to the requisite number of muscles. Why do insects fly ? Because the muscles which move their wings take their rise in the breast, and are capable of executing their functions with great celerity. The flying insects do not possess rapidity of flight proportional to the number and size of their wings. In the coleoptera, the body hangs down during flight, while in other classes it preserves nearly a horizontal position. The wings are composed of two membranes, an upper one, in which nervures or cords are traced ; a lower one, separable from the upper. These nervures or cords contain a spiral vessel, " whence they appear," says Kirby, " to be air vessels communicating with the trachea in the trunk. The expansion of the wing at the will of the insect is a problem that can only be solved, by supposing that a subtle fluid is introduced into these vessels, which seems perfectly analogous to those in the wings of birds ; and that thus an impulse is communicated to every part of the organ, sufficient to keep it in proper tension : we see by this, that a wing is supported in its flight like a sail by its cordage." Why are the wings of insects important to the natu- ralist P Because they, in a great measure, furnish the cha- racters employed in classification. Thus, the pre- sence or absence of wings their number and appen- dices their texture and consistence, together with their size, position, and manner of folding up, yield marks which are easy of detection, and which experi- ence has found to be perfect. Fleming. Why are the ujtper wings of insects called elytra or wing-cases? Because they serve as a covering to the inferior c2 232 KNOWLEDGE FOR THE PEOPLE. ones. Strictly speaking, these elytra are not wings, since they perform no other motion than elevation and depression, and serve merely to protect the wings when at rest, not to assist them when flying. Why are not aquatic insects wet with the water in which they reside P Because the skin is probably smeared with some unctuous matter ; comparative anatomy hitherto having failed in detecting any glands subservient to the func- tions of the skin. In some instances, indeed, the skin resists being wet, even after the death of the ani- mal has taken place for some time, but previous to becoming dry. Fleming. Dr. Arnott physically attributes it to the weight of the insects not being sufficient to overcome the cohesion of the particles of water among themselves. In the tribes which swim, the legs are either flat- tened like the blade of an oar, or produced and ciliated (fringed) on the edges. Some swim upon their back, others upon their belly. Some keep always floating upon the surface, others dive and perform their move- ments at various depths, regulated by the condition of the organs of respiration. Fleming. Why were insects and worms formerly called blood- less animals P Because they are distinguished from the preceding classes by the absence of red blood, in place of which they have a white fluid. In recent times, on account of the absence of vertebra? and ribs, they have received the name of Invertebral Animals. Among the crustaceous animals, as the lobster and shrimp, the blood is w 7 hite ; while, among some in- sects, as the grasshopper, and white caterpillar, it is green. Heivson, Phil. Trans. Why are insects supposed to possess a heart P Because, both in their perfect and larvae state, they have a membranous tube running along the back, in ZOOLOGY. INSECTS. 233 which alternate dilatations and contractions may be observed ; but it is closed at both ends, and no vessels can be perceived to originate from it. Why are not insects concluded to take in air through the mouth p Because they are furnished with air-vessels or tra- chea, which ramify over most of their body. These tracheae are much larger and more numerous in the larva state of such insects as undergo a metamorpho- sis (in which state also the process of nutrition is car- ried on to the greatest extent) than after the last, or, as it is called, the perfect change, has taken place. Why is the mode of respiration observable but in few insects P Because they in general breathe not by the mouth, but by many spiracula, or pores. The greater number of them can live in a vacuum much longer than red- blooded animals, and many in mephitic atmospheres, so fatal to others, and in which animal and vegetable substances become putrid. Why is the metamorphosis of insects so called P Because there is not any winged insect which es- capes from the egg as such, but all, as well as many insects which have not wings, must first undergo a kind of change, at a certain period of their existence. Such insects are called larvce> whilst in the state in which they escape from the egg. They are mostly very small on their first appearance, so that a full- grown caterpillar of the willow moth, for instance, is 72,000 times heavier than when it first issues from the egg. On the other hand, they grow with great rapi- dity, so that as an example, the maggot of the meat- fly, at the end of twenty-four hours, is 155 times hea- vier than at its birth. Laryae are incapable of propa- gating ; they merely feed, increase, and change their covering several times. The larvse become nymph. Many can move about c 3 234 KNOWLEDGE FOR THE PEOPLE. and take food in this state. Others, on the contrary, are covered up, as pupa% (chrysalides, aureliae) and pass this portion of their life in a state of torpor, without eating or moving. A great change is, however, going on, by which the animal quits its larva state, and leaves its prison a perfect insect. In popular language, a caterpillar or grub is fur- nished with feet, and a maggot or gentle is without feet. Why is the metamorphosis of insects so remarkable a branch of their economy P Because, by this, not only their external form, but also at the same time their internal structure, contrary to common opinion, is altered in a certain degree. Blumenbach remarks, if the moth existed already formed in the caterpillar, we should at least expect that similar moths should be produced by similar ca- terpillars. But many American caterpillars, which resemble European ones in the closest manner possible, give origin to moths having totally different forms ; and, on the other hand, many remarkably similar moths of both these parts of the world are developed from caterpillars altogether unlike. Why do certain larvae form an exterior covering or cocoon P Because the pupa may be lodged with greater safety. This covering is in some composed of threads of silk. Sometimes only one or two threads are required to keep the pupa in a proper position ; in others, the silk is woven into cloth, or so matted together, as to re- semble paper. The matter, of which these cases or cocoons are fabricated, is prepared by two long tubes, which take their rise in the abdomen, enlarge as they approach the head, and terminate by a duct, which opens under the labium, or lower lip. By press- ing the orifice of this duct to^one place, and then to another, the larva draws out the tenaceous threads. Fleming. ZOOLOGY. INSECTS. 235 Why is the pupa so called P Because the larva, when so inclosed, resembles an infant in swaddling hands. From the pupa? of many of the butterflies appearing gilt as if with gold, the Greeks called them Chrysalides, and the Romans Au- relice, and hence naturalists frequently call a pupa chrysalis, even when it is not gilt. Why do certain insects neither eat nor move when in the pupa state P Because they derive their nourishment from their stores of fat. Why are the larvce more voracious than the perfect insects P Because their digestive organs are of much greater dimensions than when arrived at maturity ; and in the condition of larvae, in sects possess a variety of members, as legs, suckers, hairs, and even stigmata, (respiratory organs) which they do not possess in their maturity. Fleming. Why have most of the rings of the abdomen an open pore placed laterally P Because they may serve as breathing holes, through which the fluids of the animal become aerated. The three portions of the body of insects, the trunk, head, and abdomen, in the different tribes, exhibit very remarkable combinations. In some of the crus- taceous animals, these portions are incorporated in the dorsal (or back) surface of the body. In some of the arachnida?, (or spider genus) the head and trunk are niched, while, in others, the head appears to be dis- tinct, while the trunk and abdomen are incorporated. These modifications are extensively employed in the methodical distribution of the groups. Why do insects attach their eggs to certain substances P Because the young, being hatched, are destined to feed on those substances. Thus, the butterfly attaches her eggs to a leaf; the flesh-fly deposits her's upon 236 KNOWLEDGE FOR THE PEOPLE. carrion ; while others insert them into the young of other insects. Fleming. Why are the egc/s of insects, wlien deposited in the open air, covered hy the mother with a kind of varnish P Because they may thus be protected from the de- structive influence of rain, and other accidents. Among other peculiarities of the propagation of insects, many, as the cochineal worm, the laced-flea, &c. become of an enormous size during pregnancy: thus, in the white ant, it has been calculated that the abdomen of the female, when about to lay her eggs, is 2000 times larger than previous to impregnation. Why are insects generally considered unsocial P Because only a few of them afford mutual assist- ance in their labours. The greater number follow their pursuits singly ; many, as spiders, live in society when young, but afterwards separate, and live in a state of solitude, seeing creatures of the same species only at the time of pairing. Swift very aptly observes, " suspense is the life of the spider." The labours of such insects as live in communities are, however, very remarkable ; since they thus build common residences, by their united powers, and under the guidance of an extremely regular, geometrical, innate instinct. There are but few creatures of this class which do not, at least once in their life, give proofs of this natural power of construction ; either as the cloth moth and water moth, form a habitation in their incomplete and larva state ; or, like others, spin and prepare a receptacle to contain them during their metamorphosis and death-like sleep ; or, like the lion- ant, dig pits : or. like the spider, weave webs for their prey, and bags or nets for the security of their poste- rity, and in which they deposit their eggs. All those insects which liv,e in society, when ex- posed to cold, are observed to cluster together, as if to keep each other warm. Some, indeed, when exposed ZOOLOGY. INSECTS. 237 to cold, become torpid, and revive upon the restoration of a suitable temperature ; but there are others, as the honey bee, which resist any reduction of their tempe- rature below their ordinary digestive heat, and pre- serve it in their dwellings, even during the winter season. John Hunter found a hive in July 18, at 82, when the temperature of the air was only 54 ; and in December 30, at 73, when the air was only 35. (Phil. Trans.) When cooled, until they become be- come benumbed, they seldom recover, while the wasp, belonging to the same natural order, can be rendered torpid, and again revived with safety. Why are entomological studies interesting and advan- tageous in a moral point of view P Because the analogies derived from the transforma- tion of insects admit of some beautiful applications, which have not been neglected by pious entomologists. The three states of the caterpillar, larva, and butterfly, have, since the time of the Greek poets, been applied to typify the human being ; its terrestrial form, appa- rent death, and ultimate celestial destination : and it seems more extraordinary, that a sordid and crawling worm, should become a beautiful and active fly ; that an inhabitant of the dark and fetid dunghill, should in an instant entirely change its form, rise into the blue air, and enjoy the sunbeams, than that a being, whose pursuits here have been after an undying name, and whose purest happiness has been derived from the acquisition of intellectual power and finite knowledge, should rise hereafter into a state of being, where im- mortality is no longer a name, and ascend to the source of Unbounded Power and Infinite Wisdom. Sir H. Davy Salmonia. COLEOPTERA. BEETLES. Why are insects of this tribe so often eaten by fishes P Because all such as are abundant in summer are 238 KNOWLEDGE FOR THE PEOPLE. frequently blown into the water, where they become easy prey. Thus, the brown beetle, or cockchaffer, the fern-fly, and the grey beetle, are devoured in great numbers. But there is hardly an insect that flies, in- cluding the wasp, the hornet, the bee, and the butter- fly, that does not become at some time the prey of fishes. So voracious are the grubs of some beetles,that the younger ones, when so gorged with those they have devoured, as scarcely to be able to move without burst- ing, are said, by Kirby and Spence, " often to take advantage of the helpless inactivity into which the gluttony of their maturer comrades has thrown them, and from mere wantonness, it should seem, when in no need of other food, pierce and devour them." Some beetles are, however, very abstemious. Thus, the rose-chaffer has been kept alive more than eight years, by being fed on crusts of bread soaked in water. Why was the beetle so often introduced in the build- ings of the ancient Egyptians P Because it was, to all appearance, a highly sacred animal. In the Egyptian tombs, it is found in great variety : of basalt, verde antico, or other stones, and of baked clay. Some have hieroglyphics on them, which no doubt contain some particular prayers, or the com- memoration of striking events in the life of the de- ceased. It is supposed, that the Egyptians hung the beetle to their necks when they went to war ; but of this we have no clear proofs. Belzoni mentions a circumstance which, he thinks, will solve the doubt. The beetles are of such a peculiar form, that if they were among the ornaments of the warriors, they would be easily distinguished. He observed a solitary in- stance of this kind. There is a sitting figure in the tomb of Samethis, which he discovered in the valley below Bebau el Malook, that, by its splendid dress and ornaments, may be intended Fo represent a king. It has a square plate of basalt hung to its neck, with an ZOOLOGY. INSECTS. 239 obelisk in the centre, and a figure on each side of it. He believes the above plate to be the only one that was ever found of the king. It has the form of an Egyptian temple, and in the centre is an elevated beetle on a boat, guarded by two figures, one at each side ; and, on the reverse of the beetle, is an inscription over a boat, on which are two other figures, exactly like the former. The plate has the holes by which it w ? as hung to a chain or string. Belzoni found also other beetles, with human heads, which he had never seen before. Why is the dung-beetle also called the dorr? Because, in old times, dorr was a stupid, blundering fellow ; and, to dorr, was to ding or trouble with noise ; both meanings applicable to the heedless flight, and loud noise, made in all the transits of this dung beetle. Such is the conjecture of Mr. Knapp, in his Journal of a Naturalist, who also speaks of dung beetles as clocks " as the boys call them, a corruption, he thinks, from cloax, a vault, a creature from below, which might signify its subterranean residence." Or, bur- rowing in the filth and ordure, as it does, the epithet clocca, the offspring of a common shore, or Jakes, would not have been insignificant of its origin and habits." Why is the dorr beetle thought to counterfeit death to preserve its life P Because when flying with an apparent fearlessness of harm, if touched, or interrupted, though in no way injured, it will immediately fall to the ground, gene- rally prostrate on its back, its limbs extended, stiff, and seemingly devoid of life, and suffering itself to be handled without manifesting any signs of anima- tion. In time, finding no harm ensues, it resumes its former state. The small grey beetle, so well-known for making pin-holes in old furniture, is, however, one of the most 240 KNOWLEDGE FOR THE PEOPLE. common instances of this habit; and when it does so, it equals, if it does not exceed, the heroic firmness of the American savages, in bearing torture. You may maim these death-counterfeiting insects, pull them limb from limb, and even roast them over a slow fire, without making them move a joint, or exhibit the slightest symptom of suffering pain. Why is an abundance of the larvae of the cockchaffer to be feared P Because, while in this state, lasting four years, they feed on the roots of corn, &c. and have occasionally produced great scarcity. An instance of its ravages, as well as a specimen of notable folly on the part of the sufferers by its rapacity, occurred in 1479, when this insect was cited by a regular Monitorium before the Spiritual Court of Lausanne, who assigned it an advocate from Friburg ; but, after an attentive hearing of both parties, and mature deliberation, concluded by placing it under a ban. Why have insects of the sylph family been reputed to dig under dead mice and moles, and bury them, in order to feast on them more securely P Because they feed on maggots and their pupae; and in penetrating the ground in search of the last of these, they loosen the soil so much, that the dead animal sinks under the surface, by its own weight, or, if light, is elevated on a hillock. Fleming. Why is the tortoise-beetle so called P Because it is of the form of a tortoise, the wing cases projecting all around as a covering for the legs. Why is the diamond-beetle so called P Because it is one of the most splendid insects : the gold and colours in the numerous pits marked in rows upon the wing coverings, giving it an expressibly fine appearance in a clear light, and particularly under a magnifying glass. ZOOLOGY. INSECTS. 241 Why is the great water-beetle probably the most fero- cious creature of the pool P Because it has great muscular power, a thick and horny case over its body, eyes large enough to see all the ereatures about it, and powerful mandibles to seize and reduce them to fragments. It riots the polyphe- mus of the pool ; and having thinned its herd in one place, is supplied with wings to effect a removal to a fold better furnished. In the larva state, it is almost equally destructive : it swims admirably its hinder legs are long and brawny beside being aided by a fringe of hairs, so that they are powerful oars to propel the body with celerity and ease. Knapp. Why is the oil-beetle so called P Because of the oily-looking fluid which oozes from it when seized or alarmed. Another beetle is popu- larly called bloody-nosed, from its ejecting a red fluid from its mouth when caught : it is a very slow walker, but has an admirable contrivance for taking hold of trailing plants, on which it feeds. This consists of cushions of slightly concave thick soft hair, which both adheres by its points, and also produces some- what of a vacuum, which enables it to walk as easily with its head perpendicularly downwards as upwards. Why is the stag-beetle so called P Because the male has forceps on the head resemb- ling the antlers of the stag. Why has the rhinoceros-beetle grub been selected as a specimen of moulting P Because it is not the external skin only that these grubs cast, like serpents ; but the throat, and part of the stomach, and even the inward surface of the great gut change their skin at the same time. Yet this is not the whole of these wonders ; for, at the same time, some hundreds of breathing pipes, within the body of the grub, cast also each its delicate and tender skin. Swammerdam. 242 KNOWLEDGE FOR THE PEOPLE. DERMESTES. Why is a species of Dermestes so formidable to the pine forests of Germany P Because it lodges in such numbers in the alburnum of the pine, that 80,000 of its larvae have been counted in a tree of moderate size. This affection causes the tree to perish from the summit downwards, its leaves turn red, it loses its resin, and is rendered nearly unfit even for making charcoal, much less timber or fire- wood. This, or a similar insect, has destroyed some of the finest trees in St. James's and the Green Parks, London, although the cause was, for some time, totally unsuspected. Blumenbach. THE DEATH-WATCH. Why is a certain insect called the Death- Watch P Because of its clicking noise, chiefly in the latter end of spring, which may be considered analogous to the call of birds. This is caused by beating on hard substances with the shield or fore-part of its head. The general number of successive distinct strokes is from seven to nine, or eleven. These are given in pretty quick succession, and are repeated at uncertain intervals. In old houses, where the insects are nume- rous, they may be heard, if the weather be warm, almost every hour in the day. In beating, the insect raises itself upon its hinder legs, and, with the body somewhat inclined, beats its head, with great force and agility, against the place on which it stands. This insect, which is the real death-watch of the vulgar, must not be confounded with a minuter insect, not much unlike a louse, which makes a ticking noise like a watch ; but, instead of beating at intervals, it con- tinues its noise for a considerable length of time with- out intermission. This latter insect belongs to a very different tribe. It is usually found in old wood, de- cayed furniture, museums, and neglected books.* Phi- * Mr. Carpenter; mentioned at p. 223. ZOOLOGY. INSECTS. 243 losopliers and wits have written on the habits of this insect. That grave and good man, Sir Thomas Browne, who wrote a book on Vulgar Errors, remarks, with great seriousness, that the man " who could era- dicate this error from the minds of the people, might prevent the fearful passions of the heart, and many cold sweats taking place in grandmothers and nurses." Baxter, in his World of Spirits, observes : " There are many things that ignorance causeth multitudes to take for prodigies. I have had many discreet friends that have been affrighted with the noise called a Death- Watch ; whereas, I have since, near three years ago, oft found, by trial, that it is a noise made upon paper by a little, nimble, running worm, just like a louse, but whiter and quicker ; and it is, most usually, behind a paper pasted to a wall, especially to wainscot ; and it is rarely if ever met with but in the heat of sum- mer." In the British Apollo, 1710, is the following query : " Why Death-Watches, Crickets, and Weasels do come more common against death than any other time ? A. We look upon all such things as idle super- stitions; for, were any thing in them, bakers, brewers, inhabitants of old houses, &c. were in a melancholy condition." Duncan Campbell, in his Secret Memoirs, 1732, says, " How many people have I seen in the most terrible palpitations, for months together, expecting every hour the approach of some calamity, only by a little worm, which breeds in old wainscot, &c. endea- vouring to eat its way out, makes a noise like the movement of a watch." Grose also tells us that " the clicking of a death-watch is an omen of the death of some one in the house wherein it is heard." Swift, on the other hand, has let fly the shafts of satire, as well as furnished a charm to avert the omen, as fol- lows : " A. wood -worm, That lies in old wood, like a hare in her form, With teeth, or with claws, it will bite or will scratch ; And chambermaids christen this worm a Death-Watch, 244 KNOWLEDGE FOR THE PEOPLE. Because, like a watch, it always cries click ; Then woe be to those in the house who are sick : For, sure as a gun, they will give up the ghost, If the maggot cries click, when it scratches the post. But a kettle of scalding hot water injected, Infallibly cures the timber affected ; The omen is broken, the danger is over, The maggot will die, and the sick will recover." What an amusing treatise could Swift have written on the dry-rot: his charm, in this instance, is even more effectual than the cauldron in Macbeth. Gay, too, in a pastoral dirge, says : " The wether's bell, Before the drooping flock, toll'd forth her knell ; The solemn death-watch clicked the hour she died." WATER-FLEA. Why is the water-flea so called P Because his abode is in quiet, still water; though, in mild weather, we see him gamboling upon the sur- face of the sheltered pool, in his shining black jacket. Retiring in the autumn, and reposing all the winter in the mud at the bottom of the pond, he awakens in the spring, rises to the surface, and commences his summer sports. They associate in small parties of ten or a dozen, near the bank, where some little projection forms a bay, or renders the water particularly tranquil ; and here they will encircle round each other without contention, each in his sphere, and with no apparent object, from morning until night, with great spright- liness and animation ; and so lightly do they move on the fluid, as to form only some faint and transient cir- cles on its surface. Knapp. LADY-BIRD. Why is the lady-bird so beneficial to the gardener and husbandman P Because all the species, both in the larva and the perfect state, feed exclusively^ on aphides, and never touch vegetable substances. The eggs are usually ZOOLOGY. INSECTS. 245 placed in a group of twenty or more upon a leaf, where aphides abound ; and when the young are hatched, they find themselves in the midst of their prey. J. Rennie. This, as well as some species of Meloe, has been recommended as a remedy for the tooth-ache. Blu- menbach. THE WEEVIL. Why is the larva of the weevil prized in India P Because it feeds on the pith of sago, and is eaten itself as a delicacy. Why are weevils so destructive to wheat in granaries P Because of their fecundity, and the extraordinary manner in which they are produced. Thus, the fe- male perforates a grain of wheat or barley with the jaws placed at the end of her long proboscis, and de- posits a single egg within it; and when the young grub is excluded from the egg, it thus finds provided a fit dwelling and a store of proper food. The parent insect thus deposits its eggs in five or six grains every day, for several successive days. In about seven days' time, the larva is excluded from the egg, and, after feeding its accustomed time, changes into the chrysalis within the grain, and, in about a fortnight afterwards, comes forth a perfect weevil. The parent insect, after depositing its eggs in situations where there would be a supply for the sustenance of its offspring, does not die, but, according to Leuwenhoek, they live throughout the summer and w inter ; and they feed voraciously on the interior of the grain, both in the larva and per- fect insect state. Kirby states, that a single pair of these insects may, in one year, produce above 6,000 descendants. Why is it recommended to establish a colony of ants near a granary attacked as above P Because the ants being continually engaged in D3 246 KNOWLEDGE FOR THE PEOPLE. searching for food, would soon find their way into the interior of the granary, and feed upon the larvae of the weevils. THE GLOW-WORM. Why do the females of the gloiv-worm occasionally conceal or eclipse their light P Because they may secure themselves from becom- ing the prey of the nightingale or other nocturnal birds. Mr. White, indeed, thought that they regularly extinguished their torch between the hours of eleven and twelve. The light of the glow-worm may perhaps, occasionally deter its insect enemies from making an attack on it, as the wolf and other ravenous beasts of prey are deterred from making an approach on travellers by night, when encircled by fire. John Murray. Why has not the male glow-worm upward or side vision P Because the head is margined with a horny band, or plate, under which the eyes are situate. This pre- vents all upward vision ; and blinds, or winkers, are so fixed at the sides of his eyes, as greatly to impede the view of all lateral objects. The chief end of this creature in his nightly peregrinations, is to seek his mate, always beneath him on the earth ; and hence his apparatus appears designed to facilitate his search, confining his view entirely to what is before him or beneath him. The first serves to direct his flight, the others present the object of his pursuit : and, as we commonly, and with advantage, place our hand over the brow, to obstruct the rays of light falling from above, which enables us to see clearer an object on the ground, so must the projecting hood of this crea- ture converge the visual rays to a point beneath. Knapp. Why does the female glow-worm shine more vividly than the male P Because, this distinction being especially noticebale ZOOLOGY. INSECTS. 247 at the season of love, it is probable that the light serves the purpose of directing the male to her. Some time after the female has laid her eggs, which also shine in the dark, this light disappears in both sexes. jBlumcnbach. This theory of the light of the glow-worm has, it is feared, more poetical prettiness than truth. Mr. Ren- nie, (whose observant genius has raised him to the Pro- fessorship of Natural History, in King's College, Lon- dan,) has lately communicated such facts to the Jour- nal of the Royal Institution, as must convince the reader of the fallacy of the above. Unfortunately, the grubs, which being in a state of infancy, are there- fore incapable of propagating exhibit a no less bril- liant light than the perfect insect. De Geer says the light of the grub was paler. He also remarked the same light in the nymph state, which he describes as " very lively and brilliant ;" and in this stage of existence it is still less capable of propagating than in that of larva. " Of what use then," lie asks, " is the light displayed by the glow-worm ? It must serve some purpose yet unknown. The authors who have spoken of the male glow-worms say positively that they shine in the dark as well as the females." We must devote a page or two to the economy of this very interesting creature, which every body knows by name, but comparatively few have seen. A corres- pondent of the Philosophical Magazine describes it as follows : " The female deposits her eggs in the month of June or July, among moss, grass, &c. These eggs are of a yellow colour, and emit light. After remain- ing about five or six weeks, the larvae break their shells and make their appearance ; at first they appeal- white, and are very small, but they soon increase in size, and their colour changes to a dark brown, or nearly black. The body of the larva is formed of ele- ven rings. It has six feet, and two rows of reddish spots down the back. It emits light in the dark ; this 248 KNOWLEDGE FOR THE PEOPLE. light arises from the last ring of its body under the tail, and appears like two brilliant spots when atten- tively examined. The larvae are seen creeping about and shining during the fine nights of autumn, and the light they emit is to direct them to their food. They feed on small snails, the carcases of insects, &c. They frequently cast off their skins : after the expiration of about one year and nine months from their birth, they arrive at their perfect size. They then cease to eat, cast off their skin, and assume another appearance. The form of the perfect insect may be discovered through a thin skin that covers them. After remain- ing in this state two or three weeks, (scarcely ever moving,) they throw off their last skin, and arrive at perfection. The male then appears a perfect beetle, with wings and cover, to the same. The female, on the contrary, has neither wings, nor wing-cases ; she is larger than the male, and of a lighter colour. It is the female that principally shines in a perfect state. Her light is far superior to that emitted by the larvae, and arises from the three last rings of the body on the lower side."* Numerous opinions have obtained on the proximate cause or source of this curious illumination ; and several experiments and observations to determine this point will be found collected in a small volume of Experimental Researches, by John Murray, F.S.A. F.L.S., &c. We have not space for the details, but quote the corollaries deduced from them by this inge- nious observer: 1. Light, as connected with the glow-worm, is a subtle, evanescent principle, perhaps connected with a peculiar organized structure, or attached to a sub- stance circumfused round the vitellula of the ovum, or integrating with it ; unsupported by any chemical action, and confinable by the transparent film, or capsule, which imprisons it. 2. This light is perma- *Phil. Mag. vol.lviii,p. 53. ZOOLOGY. INSECTS. 249 nent, and independent of any power possessed by the insect over it, except in so far as it can withdraw the luminous matter from the window, or transparent me- dium, through which it is discerned, burying it in the interstitial matter, or secreting it under an opaque shell. 3. The light is not connected with any of the functions of animal life as to its supporter continuance, as with the spiracula, or breathing apparatus, and even the extinction of life itself does not extinguish the power and property of emitting light. 4. The lumi- nous matter is not adherent exteriorly, but included in a capsule, which preserves it from extrinsic agency and contingency. 5. The light seems connected with peculiar organization, which elevated temperatures destroy, perhaps by decomposition, but which low tem- peratures only suspend temporarily. This very sus- pension, indeed, by cold, and restoration by warmth, and by a temperature equal to that of animal heat, goes far to prove a peculiar function, inherent in the capsule, and capable of educing and sustaining the phenomenon." Mr. Murray thus concludes : " The use to which it is subservient in the animal economy, it is difficult to ascertain c we see but in part.' Its very existence, however, proves that it is a condition indispensable to its being. Providence has tipt the insect with living fire a non-material ignition burning, yet not consumed even extinguished by a temperature which the animal system, with which it is so singularly interwoven, cannot withstand. It may be a ' lamp to its path,' to guide it to its food, subserving the additional purpose of warding off its enemies while it may also be the luminous point that directs the nightingale to its proper prey." Why is the larva of the glow-ivorm proverbial for its cleanliness P Because it has an instrument at the tail consisting of white cartilaginous rays, disposed in a circle, one row within another, and retractile similar to the horns of a snail, which the insect employs for cleans- 250 KNOWLEDGE FOR THE PEOPLE. ing "itself. This contrivance operates by suction, and not as a comb, brush, or wiper, and is furnished with a sort of funnel-shaped pocket, formed hy the con- verging rays, into which are collected dust, &c. from the body, and the accumulated pellet is then extruded, and carefully placed where it might be out of the way of again soiling the glossy skin of the insect. This skin is of a soft leathery appearance ; exhibiting, when magnified, a minute delicate dotting, similar to shagreen. The instrument being expanded over this shagreened surface, is drawn out with an evident effort, in the same way as boys draw the moist leather suckers, when they amuse them in dragging stones after them. All dust, &c. is then detached from the skin, and by a peculiar movement of the retractile rays, is lodged in the funnel-shaped pocket. This instru- ment also assists the animal to walk, and particularly to maintain a position against gravity, which its feet are ill calculated to effect. Mr. Rennie, in Journ. Royal Instit. (abridged.) Why is the lampyris. or fire-fly, so highly prized in India ? Because the Indians believe them to be the spirits of their departed ancestors. Sir James E. Smith in- forms us that the beaux of Italy sometimes adorn the head-dresses of the belles with these " stars of the earth and diamonds of the night." Mr. Murray also says, " I remember, one fine night, on coming from Arqua (once the residence of Petrarch) to Padua, that the whole trees and hedges, to the very summit, were illuminated with myriads of these living diamonds the effect was magically magnificent." Why is the bay a bird of India supposed to light his nest with fireflies /* Because he catches the flies at night, and confines them with moist clay or cow dung. Bishop Heber says, " as the light of the flics could be of little use ZOOLOGY. INSECTS. 251 to the baya, it seems probable that he only feeds on them." THE SKIPPER. Why is the skipper so called P Because of the singular dexterity with which, when lying on its back, it throws itself into the air, and falls on its feet. Why is the light of the skipper superior to that of the glow-worm P Because it is emitted from two protuberant, trans- parent, or windowed tubercles attached to its thorax, besides which there are two luminous spots beneath the elytra, only visible, of course, when it is on wing, and they are elevated : it then appears studded with four rich and vivid gems of a golden, blue lustre. In fact, the whole body seems a flood of pure light. In the West Indies, the natives employ these living fires to give light in managing their household concerns. In travelling, they are wont to attach one to each toe ; and it is stated that in fishing and hunting they re- quire no other illumination. /. Murray. THE EARWIG. Why is the eanvig so called P Because of its supposed predilection for entering the human ear. Whether or not they ever did enter the human ear is doubtful, that they might endeavour to do so, under the influence of fear, is more than proba- ble ; and this, perhaps, has been the origin of their name, and the universal prejudice against them. As it is said that anatomists deny the possibility of their deep or dangerous entrance into the ear, it is a pity that this is not generally known, as it might defend the constitutionally timid from unnecessary alarm. Branded Journal. Earwigs, spiders, bees, and wood-lice, are amongst the few of the insect tribes which pay attention either to their eggs or offspring. 252 KNOWLEDGE FOR THE PEOPLE. HEMIPTERA. THE MANTIS. Why are certain insects termed walking leaves P Because their wing-cases, not only in colour, but in texture, and even in veining, are so exactly like leaves, from the fresh green of those newly expanded, to the faded brown of those withered and fallen, that botanists themselves might be deceived, if they were detached from the insects, and exhibited as real leaves. Among locusts alone we find the various species with wing-cases resembling, in this manner, the leaves of the laurel, the myrtle, the citron, the lily, the sage, the olive, the camellia, thyme, and grass. The spec- tres, on the other hand, resemble the small branches of trees with their spray ; and so minutely detailed is this mimicry, that the very snags and knobs, as Kirby and Spence remark, are accurately imitated. The caterpillar of the swallow-tail moth also resembles a walking branch, the ringed bulgings of the body being precisely like those of an elder branch, while the lon- gitudinal stripes are like the cracks in the bark. The mantis of this tribe is found in China and South America, and in the latter country many of the Indians believe that mantes grow on trees like leaves, and that having arrived at maturity, they loosen them- selves, and crawl or fly away. Why is this species also called the religious or praying mantis P Because it is of slender shape, and in its sitting posture holds up the two fore-legs slightly bent, as if in an attitude of prayer ; whence vulgar superstition has held it as a sacred insect ; and a popular notion has prevailed, that a child or a traveller having lost his way, would be safely directed, by observing the quarter to which the animal pointed, when taken into the hand. According to the latest classification, mantes have been divided into the two families of the mantida and ZOOLOGY. INSECTS. 253 phasmida, founded on a difference in the structure of the foot or leg ; this member, in the former, being raptorious, is provided with a sharp claw, and a hol- low on the leg and thigh, and a double series of spurs, for the better securing its prey ; and in the latter, being destitute of any such peculiarity. One of the species, ( gongylodes ) when alive and fresh, resembles a blade of grass, differing in colour according to the season, being green and succulent in the rains, and in dry weather so much like a withered straw, that it can with difficulty be distinguished. They are very ferocious, and in China the fighting mantis forms as much the favourite amusement of boys, who carry them about in cages for the purpose, as cock-fighting in England. Trans. Asiatic Soc. Calcutta. THE CRICKET. Why do we use the simile, " merry as a cricket ?" Because, quitting its summer abode, about the end of August, and fixing its residence by the fireside of kitchens or cottages, the cricket is as merry at Christ- mas, as other insects in the dog-days. Herrick, among the pleasures of a country life, quaintly sings to his brother, Yet can thy roof maintain a quire, Of singing crickets by thy fire And the brisk mouse may feast herself with crumbs, Till that the green-eyed killing comes. The grasshopper and cricket race effect their well- known and often wearisome chirpings by grating their spiny thighs against their rigid wings. LOCUSTS. Why are locusts the scourge of oriental countries P Because their devastations are so formidable, as sometimes to cause general scarcity and famine. They have likewise swarmed in Europe. In 1748 they ap- peared, but did not propagate, in England. In 1650, a cloud of locusts entered Russia, and afterwards 254 KNOWLEDGE FOR THE PEOPLE. spread over Poland and Lithuania, so as to darken the air and cover the earth, when dead, in some places, to the depth of four feet ; the trees bent with their weight. In the year 591, an army of unusually large locusts ravaged Italy, and being at last cast into the sea, (as seems for the most part to be their fate) a pestilence, it is alleged, arose from their stench, which carried off nearly a million of men and beasts. In the Venetian territory, likewise, in 1478, more than 30,000 persons are said to have perished in a famine chiefly occasioned by the depredations of locusts. Why are these insects called the locusts of scripture P Because they are the species so accurately described in the Bible. Thus, in Joel ii. 2, &c. " A fire devour- eth before them, and behind them a flame burneth : the land is as the garden of Eden before them, and behind them a desolate wilderness ; yea, and nothing shall escape them. The sound of their wings is as the sound of chariots, of many horses running to battle ; on the tops of the mountains shall they leap, like the noise of a flame of fire that devoureth stubble, as a strong people set in battle array. Before their faces the people shall be much pained ; all faces shall gather blackness. They shall run like mighty men ; they shall climb the wall like men of war ; and they shall march every one in his ways, and they shall not break their ranks ; neither shall one thrust another." Why has so much controversy arisen on " locusts and wild honey" the food of John the Baptist, in the wil- derness P Because the commentators have interpreted the former as the fruit of the cassia-fistula, or locust-tree, resembling tamarinds; and other substitutes. Dr. Clarke, the traveller, was one of the first to propagate this misconception. There is, however, no doubt of the insects being the food, sirice Hasselquist mentions locusts being eaten by the Arabs, so that probably this ZOOLOGY. INSECTS. 255 dish was used in the time of St. John. Mr. Forbes, the Oriental traveller, corroborates this account, and adds, " The wild honey is found in the clefts of the rocks of Judea, as abundantly as in the caves of Hindustan." THE LANTERN FLY. Why is the lantern fly so called P Because it emits a strong light from a horny bladder on the head, almost as large as the whole body, so that the natives of Guinea use them as lanterns. The light, according to Mad. Merian, is sufficient to read a newspaper by. THE FROTH WORM. Why is white froth so frequently seen in summer on willoivs, rose-trees, grass, fyc. P Because it is thrown up by the larva of the cuckoo- spit frog-hopper, as a protection from the sun, the creature being exceedingly soft. The name of " cuckoo- spit" is therefore a popular mistake. APHIDES. Why do aphides or plant lice increase so rapidly P Because one impregnation not only renders fertile the eggs of the individual, but the animals produced from these, and the eggs of these again, unto the ninth generation. Philos. Transactions. Why are the aphides, so of ten seen on apple-trees, called white blight P Because they are lodged upon the limbs of the trees in a hoary and cottony substance, beneath which these wingless creatures prey upon the tree by means of a beak terminating in a fine bristle : this being in- sinuated through the bark and the sappy part of the wood, enables the creature to extract, as with a sy- ringe, the sweet vital liquor that circulates in the plant, till the tree perishes limb by limb. This insect produces its young alive, forming a cradle for them by E2 250 KNOWLEDGE FOU THE PEOPLE. discharging from the extremities of its body a quan- tity of long cottony matter, which becoming inter- woven and entangled, prevents the young from falling to the earth, completely envelopes the parent and off- spring, and serves as a vehicle for dispersing the wing- less animal in tufts wafted by the winds from tree to tree throughout the whole orchard. When the long cottony vesture is removed, the insects are still enve- loped in a fine short downy clothing, to be seen by a magnifier, proceeding apparently from every suture or pore of their bodies, and protecting them in their dormant state from the moisture and frosts of our climate. Mr. Knapp thinks the epithet, ' American blight,' may be correctly applied to this insect, but we have no sufficient authority to conclude that we de- rived the pest from that country. Why are aphides never seen in the flower of the rose, although they infest the stalk leaves P Because of the odour of the flower. Why are the larvae of lace-ivinged flies called the lions of aphides P Because they devour the latter with great voracity, sucking the juices of their victims with their crescent- shaped and hollow mandibles. The transparent wings of some insects are so atten- uated in their structure, that 50,000 of them, placed over each other, would not form a pile a quarter of an inch in height. KERMES AND LAC. Why is the kermes so highly prized P Because, in the south of Europe, where it is found, on holly, carmine is prepared by sprinkling vinegar on the berry or gall-shaped nests of this animal's eggs. Wliy is gum-lac so called P * Because it is the produce of the lac-insect, on the hilly parts of Hindostan. Blumenbach says, " a white ZOOLOGY INSECTS. 257 wax-like kind of lac lias lately been found in Madras, the specimens of which, in my possession, consist of single cells, resembling coffee-berries in size and shape ; it may prove very valuable in India, where bees'-wax is scarce." Although Blumenbach states this as a recent discovery, Dr. Pearson, in 1794, ob- tained from the same substance, or white lac, a pecu- liar acid, which he called laccic acid. Lac appears designed to answer the purpose of de- fending the eggs of the insect from injury, and af- fording food for the maggot in a more advanced state. COCHINEAL INSECT. Why was the cochineal insect originally supposed to be a grain or seed ? Because, during the whole term of its life, it re- mains fixed to the spot where it first settled, and to the vegetable nipple of the nopal plant which feeds it. Why are these insects propagated with such rapidity P Because the nopal plant is inoculated with them, by being rubbed with a small portion of the young resembling blight, and, in proportion as the plant in- creases its leaves, it is sure to be covered with this costly parasite. When the plant is perfectly saturated, the cochineal is scraped off with great care. Planta- tions containing fifty or sixty thousand trees, growing in straight lines, may be seen in some districts of America. The quantity of insects annually exported from South America is valued at 500,000/. The Spanish Government are jealous of its being natural- ized elsewhere, while a reward of 6,000/. is offered by the East India Company for its introduction into our territories.* Cochineal has been transplanted to Java and old Spain, with great success, and on the island of Malta. The wild species of cochineal, or kermes, *The duty on cochineal imported from British possessions is 2