IRLF THE LIBRARY OF THE UNIVERSITY OF CALIFORNIA PRESENTED BY PROF. CHARLES A. KOFOID AND MRS. PRUDENCE W. KOFOID OUR HOUSEHOLD INSECTS OUR HOUSEHOLD INSECTS AN ACCOUNT OF THE INSECT-PESTS FOUND IN DWELLING-HOUSES BY EDWAKD A. BUTLER, B.A., B.Sc. (LoND.) AUTHOR OP "POND-LIFE," "SILKWORMS," ETC. LONDON LONGMANS, GKEEN, AND CO. AND NEW YOEK: 15 EAST 16 tb STEEET 1893 All rights reserved PREFACE. THE contents of this book originally appeared as a series of articles in Knowledge, and I am indebted to the courtesy of the editor and proprietors of that journal for their re-issue in the present form. My aim has been to give a plain and easy account of such insect pests as may be met with in ordinary dwelling- houses, and thus to show that every one has ready to hand, with very little trouble in the way of collection, abundant material for the practical study of that most fascinating branch of natural history, entomology. As the book is written primarily for those who have no special knowledge of the subject, I have endeavoured to put the descriptions of insect structure into ordinary language as far as possible, and to abstain from the unnecessary introduction of technicalities. Where tech- nical terms have been of necessity used, an attempt has been made to explain each on its first introduction. Though the book is intended primarily for the novice, I would yet venture to hope that it may be of some service to more advanced students of entomology, as bringing into one volume items of information that 5 vi PREFACE at present exist scattered throughout the vast mass of entomological literature. The arrangement of the matter was necessarily determined to a great extent by the method of the original issue as a series of detached articles ; had the work been written for publication in the present form, the plan would have been somewhat modified and made more systematic. The seven page-plates have been made from photo- graphic enlargements prepared for the oxy-hydrogen lantern by Messrs. F. Newton & Co. of No. 3 Fleet Street, London, who have kindly lent the negatives for the purpose. E. A. B. CONTENTS. CHAP. PAGE I. WOOD-BOEING BEETLES ....". . I II. CLUB-HOKN BEETLES . . . . . . 22 III. CELLAR BEETLES AND MEAL WORMS . . -32 IV. LONGHORNS AND PREY-HUNTERS .... 46 V. ANTS AND WASPS . 55 VI. SOCIAL WASPS AND HORNTAILS .... 66 VII. CLOTHES MOTHS AND OTHER TINE^ . . .89 VIII. MEAL AND TABBY MOTHS . . . . .107 IX. THE COMMON COCKROACH Il6 X. CRICKETS AND EARWIGS . . . . . . 147 XI. HOUSE FLIES AND BLUEBOTTLES . . . .172 XII. HOUSE FLIES AND BLUEBOTTLES continued . -195 XIII. GNATS, MIDGES, AND MOSQUITOES . . .221 XIV. THE COMMON FLEA .... . . . 248 XV. THE BED-BUG . . 273 XVI. THE BOOK-LOUSE AND SILVER-FISH INSECT . . 304 XVII. HUMAN PEDICULI 325 INDEX 343 vii LIST OF PLATES. PLATE I. PORTIONS OF CORNEA OF FLY'S COMPOUND EYE AND FLY'S FOOT . . . Frontispiece PLATE II. FLY'S "PROBOSCIS," AND PORTION OF ONE LABELLA OF SAME . . . . To face p. K)2 PLATE III. MALE AND FEMALE GNAT 225 PLATE IV. LARVA AND PUPA OF GNAT . . 2 3 PLATE V. MALE AND FEMALE FLEA . . . . . . 258 PLATE VI. BED-BUG . j.^-i ---- '- ' 2 86 PLATE VII. TRACHEA OF SILKWORM AND WATER-BEETLE . 296 OUR HOUSEHOLD INSECTS. CHAPTER I. WOOD-BORING BEETLES. MAN is accompanied in his migrations, not merely by what are familiarly known as the "domestic animals," but also by hosts of insects, which find improved means of subsistence by linking their fortunes with his, and which, though often causing him infinite annoyance, sometimes render considerable, though generally un- recognised and unappreciated services. In their persis- tent accompaniment of their lord and master, some have travelled over vast areas of land and sea, getting free passages in all the navies of the world ; and we in this country owe several of our commonest insects to our. commerce with foreign nations. It is " cupboard love " that impels insects to accompany man : they follow him for what they can get; his food they pilfer; his heirlooms they destroy ; his house, his furniture, his clothes, they attack ; and even his very person is not held sacred, especially if he himself so sins against nature as to violate the laws of cleanliness and health. So, not an abode can be found whether of the most degraded barbarian on the one hand, or of the very cream of civilised society on the other which can boast A 2 OUR HOUSEHOLD INSECTS of immunity from the intrusion of representatives of this immense horde of living creatures. That some of this vast host should have special re- lations to mankind is not to be wondered at, when we remember that two of the chief functions of insect life in the world seem to be the repression of superabundant vegetation, and the removal of effete and waste matters ; for while man in his agricultural capacity bids mother earth bring forth the "herb yielding seed after his kind " more and more abundantly, he often finds a serious ch,eck to his efforts in the mighty hosts of insects which the very success of his agricultural opera- tions has been the means of vastly increasing; and, again, while in his constructive and manufacturing capacity he is busily engaged in converting natural products of the animal and vegetable worlds into things suitable for his own use, he thereby attracts the scavenger hosts, who, evidently regarding his ac- cumulations of manufactured articles as so much lumber to be got rid of as quickly as may be, set to work on his cherished hoards with right good will, and tax all his ingenuity to save them from ruin. So it comes to pass that there are many species of insects that more .or less permanently take up their abode with us, either actually in our houses and outbuildings, or in our culti- vated lands, and depend in large degree upon us and our belongings for their support. It is only with the former of these groups that we propose to deal, but we shall find in them good representatives of insect life in general ; and any one may obtain excellent material for the practical study of entomology and the examination of insect structure without going beyond the four walls of an ordinary dwelling-house. As there are some animal pests found in houses WOOD-BORING BEETLES 3 that are often called insects, though not really such, it will be best first of all briefly to indicate what kind of creature is implied zoologically by the term "insect." Insects constitute a class of the animal kingdom dis- tinguished from other invertebrate animals by having the body divided into three parts, head, thorax, and abdomen, and by possessing in the adult condition six legs disposed in three pairs, and usually four wings as well. The head carries first the mouth organs, which vary much in different groups, and will be particularly described hereafter, and secondly the organs of sense, consisting chiefly of the eyes and antennae, the latter being that pair of long jointed appendages popularly known as " horns." The thorax carries the legs beneath and the wings above. The abdomen carries no legs in the adult insect, but has frequently in the females a more or less complicated apparatus at the end, some- times looking like a long tail, and used for depositing the eggs, and therefore called an ovipositor. Most insects also pass through a series of transformations during the course of their life, which are called col- lectively "metamorphoses." They are first the egg; secondly the larva, grub, or caterpillar; thirdly the chrysalis or pupa; and fourthly the perfect insect or imago. There are other characteristics of a less obvious nature, but these are in most cases sufficient for practical purposes, and will enable one to determine what animals are insects and what are not. The class is subdivided, according to the nature of the wings, the feeding appa- ratus, and the life history, into groups called " orders ; " and our household insects are so varied in structure that there is not a single important order unrepresented in domestic entomology. 4 OUR HOUSEHOLD INSECTS We will turn our attention first to that order which is usually placed at the head of the class, viz., the Coleoptera, or Beetles. Of these, a considerable variety make our houses their foraging quarters, and one of the most important sec- tions is that of the " Wood-borers." These often commit great depredations in the beams and other woodwork used in the framework of houses, as well as in articles of furniture, producing the result known as "worm- eaten." Formerly, their ravages were more considerable than at the present day, owing to the then more exten- sive use of timber (and especially unpainted timber) in building construction. The external indications of the presence of these destructive insects are usually twofold : small circular perforations in the surface of the wood, and little heaps of yellow dust on the ground beneath them. The perforations are the entrances to, or rather exits from, long cylindrical tunnels traversing the wood in various directions, generally in that of its length, and often to so great an extent as to leave only the narrowest of partitions between them, and so reduce the whole interior to a mere network, which is so fragile as to crumble away on the slightest touch, while the outside still remains intact, except for the few perforations, and gives the wood the appearance of being almost as sound as when first put up. The beetles themselves are not so often seen, as they spend a large proportion of their life in their burrows. Their ravages are similar in result to those of the shipworm upon submerged timber, though the latter animal belongs to the Mollusca, and is a relative of such animals as the mussel, oyster, &c. Several species of beetles are answerable for these damages; the commonest is a small cylindrical insect WOOD-BORING BEETLES 5 called Anobium domesticum (Fig. i). It is scarcely one- sixth of an inch long, of a dark brown colour, and, like most of its allies, has the head much sunk in the thorax, which is raised be- hind into a protu- FIG. i. Anobium domesticum. berance in such a way as to cause it to resemble a hood or cowl. When viewed sideways this has a most quaint appearance, and irresistibly reminds one of a coal-scuttle bonnet almost entirely enveloping the head. The upper pair of wings are in the form of hard horny pieces, quite useless for flight, and employed only to cover and protect the delicate membranous hind-wings. They are called elytra, or wing-covers, and it is from this peculiarity of struc- ture that the order gets its name Coleoptera (sheath- wings). The wing-covers are marked with narrow, parallel, longitudinal furrows, and are covered with short soft hairs, termed collectively " pubescence ;" under them are folded a pair of large -sized wings. The legs are of moderate length, but can be closely packed away under the body, when the insect looks like a mere cylindrical pellet of wood, earth, or other inorganic matter, or like a miniature cartridge fitting well into the tubular burrows. In this condition it may be rolled about without manifesting signs of life. The antennae have the last three joints much larger and longer than the rest, a peculiarity which also pertains to other members of the family. In its larval condition this insect is a thick fleshy grub, somewhat curved, and swollen at each end (Fig. 2). On the anterior part of the body it carries six tiny legs, a pair on each of the three segments immediately 6 OUR HOUSEHOLD INSECTS succeeding the head. It is of a whitish colour, as might be expected in a creature which spends its time in the darkness of a tunnel ; only in the jaws, and that part FIG. 2. I^arva of Anobium domesticum (a, back view ; b, side view). of the head immediately surrounding the mouth, is any more definite colour to be found, and this part appears as a dark brownish-black spot oh the otherwise imma- culate insect. . Except in the head, the skin is soft and yielding, and a few hairs are scattered along its sides. These larvae are very seldom seen, as, in order to get at them, the wood in which they are domiciled must be pulled to pieces. Their food consists of the wood itself, which by their powerful though tiny jaws is bitten off in minute particles, many of which, however, are left un- eaten, and either clog up the burrows or are ejected at their openings, where they constitute the tiny heaps of yellow dust referred to above. No wood is so old and dry that they cannot extract nourishment from it ; in fact, the older and drier it is the better they like it. An animal subsisting on such food might be expected to be a lean wiry creature of half-starved aspect, but exactly the contrary is really the case ; for these white grubs are fat and flourishing, and a full-grown one might be supposed to have been fattening up for a prize competition, for it looks as bloated as a prize pig. WOOD-BORING BEETLES They become a chrysalis in their burrows, enveloping themselves in a silken cocoon, in which are interwoven particles of the dust they make. On emerging from the chrysalis they remain inactive for some time, not coming out of their burrows, and only gradually acquiring their normal colour and consistency, and with these their activity. An insect allied to Anobium domesticum, and formerly referred to the same genus, but now known as Xesto- bium tessellatum, has often been a source of terror to the superstitious, by whom it is known as the Death Watch. It is a stout reddish-brown beetle, sprinkled with small patches of pale hairs ; but, while very similar in shape, it is a great deal larger than any of the Anobia proper, sometimes attaining a length of one-third inch, and a corresponding obesity (Fig. 3). The ticking or clicking noise that is sometimes heard in old houses, and has so often been considered to por- tend the death of some inhabitant of the dwelling within the year, is caused by these insects striking the wooden walls of their burrows with their hard heads or jaws, and is generally supposed to be a love-call, for when one has made some four or five taps in quick succession, it pauses, and is immediately answered by another in some different quarter. The tapping is not sufficiently loud to attract much attention in the daytime, when so many other noises are going on ; but in the stillness of the night, when every sound that does occur seems magnified to an enormous degree, this regular succession of knocks, proceeding from no apparent FIG. 3. Xestobium tessellatum. 8 OUR HOUSEHOLD INSECTS physical cause, might, on the principle of omne ig~ notum pro mirifico, easily awake apprehension in the minds of the ignorant and superstitious, already by habit accustomed to look out for "omens," "visita- tions," " warnings," and the like ; and it is, perhaps, not altogether to be wondered at that amongst those engaged in nursing the sick, who, from the stillness of the sick- room, and the fact of their being night-watchers, would generally be the most likely to meet with such experi- ences, some should have seen in these mysterious tap- pings a confirmation of their own anxious forebodings with respect to the loved ones of their charge. But the application of a little practical common- sense soon dis- pels these illusions, and demonstrates the very material nature of the omens, or, as Swift quaintly puts it : " A kettle of scalding hot water ejected Infallibly cures the timber affected ; The omen is broken, the danger is over, The maggot will die, and the sick will recover." In the "Philosophical Transactions" for 1698 is a curious paper entitled " An Account of the Scaraboeus Galeatus Pulsator, or the Death Watch, taken August, 1695, by Mr. Benjamin Allen." It is accompanied by an enormously magnified figure of the insect, and from this and the description, it is evident that the Scarabseus is none other than our present acquaintance ; and the article appears to be the earliest detailed scientific ac- count of the insect. The writer commences in a some- what spasmodic and inconsequent style: "The second Animal I observ'd is a Death Watch : I have taken some before this, it is that which makes a noise resem- bling exactly that of a Watch ; it is faithfully the very same, and liv'd Four Days with me, beating exactly, for WOOD-BORING BEETLES 9 I took two, I suppose one was the Female, that is only conjecture." He is a little bit sceptical as to the pro- phetic character of the tappings, saying, "This small Beetle . . . being rarely heard, and not known, has obtain'd the name of a Death Watch, which yet I have known to be heard by many, when no mortality followed, and particularly by myself, who have taken Two of the same, Seven years since, without any Death following that Year." A quarter of a century later, another ob- server, Mr. Hugh Stackhouse, communicates a further note on the subject, wisely abstaining, however, from any reference to the theory of prognostications. He prefaces the article by an account, almost needlessly minute and circumstantial, of the way in which he gra- dually tracked the insect by its ticking, till he found it in the seat of a rush-bottomed chair. Here he watched the little creature at work, and was so delighted with his discovery that he " called up others to see it beat, which they did, not without admiration." He then pro- ceeds to describe the " manner of its beating." In its helmet-like thorax or galea, as he calls it he sees " a very notable and providential defence against such falls as are frequent in rotten and decayed places." He transferred his captive to a box, and kept it alive about a fortnight, but was unable to get it to beat again during its captivity, apparently through not knowing how to induce the action, for in the Entomologist's Monthly Magazine for 1866, the late Mr. F. Smith states that he had no difficulty in getting some that he kept to tick whenever he wished, by simply tapping five or six times with a lead pencil upon the table close to the box in which they were confined. They very shortly answered the summons. Raising themselves on their front legs, they commenced bobbing their heads up and down, io OUR HOUSEHOLD INSECTS rapidly tapping with their jaws on the bottom of the box. The number of taps on each occasion was either four or five, usually the latter. The Dutch naturalist Swammerdam, who flourished during the latter half of the seventeenth century, speaks, in his " Book of Nature," of an insect, no doubt either the present or an allied species, which "makes a con- tinual noise in old pieces of wood, walls, and ceilings, which is sometimes so loud that, upon hearing it, people have been persuaded that nocturnal hobgoblins, ghosts, or fairies wandered about them." He adds, " I think this may\ be properly called Sonicephalus, or Noisy- headed Beetle." A totally different insect, known generally as the "book-louse," has also been credited with being the pro- ducer of Death Watch tappings. It is an extremely minute, soft-bodied creature, belonging to the order Neuroptera, and is a very common inhabitant of houses. But it does not seem possible that a creature of such delicate structure should create these noises; however, we will recur to this subject when, later on, we come to the consideration of the insect in question. Xestobium tessellatum, being so much larger than the Anobia, is, of course, far more destructive to timber, if allowed to have full scope for its powers. Spence speaks of the whole of the woodwork of a house in Brussels requiring to be renewed in consequence of its depreda- tions, and states that he was informed that this was no uncommon occurrence there, the inhabitants calmly acquiescing in the attacks of their tiny foe, through ignorance of any plan of exterminating it, or at any rate checking its ravages. Like most wood- feeders, it is long-lived in the larval state. Westwood kept one for three years before it attained its perfect form. WOOD-BORING BEETLES n Though Xestobium tessellatum is the principal beetle which, in this country, has been identified with Death Watch tickings, it is not alone in this claim to the character of harbinger of death. Anobium domesticum also ticks, and has, no doubt, scared many a rustic equally with Xestobium. One entomologist at least the indefatigable Professor Westwood once kept a regular diary of its tickings, the particular specimens whose doings were chronicled being inhabitants of a wooden mantel in the Professor's study. They ticked at intervals during the winter months, as well as at other seasons, though at such times the noises could scarcely have been intended, as they probably are during the warmer months, as an exchange of compliments between love-sick couples. Notwithstanding the obscurity and retirement of their life, these wood-boring beetles have not managed to escape the attacks of parasites. Several species of ichneumon flies and other allied insects prey upon them ; and the delicate little gauzy-winged persecutors may sometimes be seen running about hither and thither over Anobium-infested wood, in maternal anxiety to find a suitable nidus for their brood. Some, too large to enter the burrows, are furnished with a long ovi- positor with which to reach their victims, into whose bodies they insert their eggs. Others are small enough to enter the burrows bodily, and hunt their prey like a ferret after a rabbit. One of these latter, Theocolax formiciformis, superficially something like a minute ant, in consequence of the absence of wings, I have obtained in .considerable numbers from a colony of Anobium domestidum which had established themselves in an old aquarium stand. Yet another member of this family of wood-borers, 12 OUR HOUSEHOLD INSECTS of very similar appearance to Anobium, sometimes does considerable damage to woodwork. It is especially partial to willow-wood, in which it makes neat cylindrical burrows. It is called Ptilinus pectinicornis, and the specific name refers to a remarkable peculiarity in the antennae of the male, the sex which, for a reason that will appear presently, is most com- monly seen. It may be recog- nised by its extremely cylindrical FIG. 4 .-Ptiiirms pectinicornis reddish-brown body and rather (male). * swollen black thorax (Fig. 4). The antennas are marvellously beautiful. Instead of being composed of a mere string of simple joints, such as constitute those of the allied species, and, in fact, of beetles in general, they appear, when fully spread out, like two pieces of deep fringe. This results from each joint, except the two at the base and the one at the apex, carrying a lateral appendage generally far longer than itself. The apical joint is itself of the same form as these appendages, so that altogether there are nine of them ; but the one nearest the base is much shorter than the rest, and seems little more than like a stout tooth ; while the last seven, which are of nearly equal length, are several times as long as the joints to which they belong. Antennae of a similar character occur in a few other British beetles, though in none is the peculiarity so greatly exaggerated as in the present species. It is not easy to conjecture the raison d'etre of this remarkable feature, for there seems to be little in the habits of the insect to account for its differing from its WOOD-BORING BEETLES 13 congeners in so peculiar a way. It can scarcely be merely a sexual distinction, but seems to point to some greater acuteness in the organs of sense, perhaps necessi- tated by the fact that the female rarely leaves her burrows, only advancing to the entrance thereof to receive the addresses of her lord and master, who, on his part, remains on the outside, and conducts his court- ship from that position. It is a curious fact that the males of certain moths, which have similarly complex antennae, possess also a marvellous power, quite inde- pendent of sight, of detecting, even from great distances, the presence of a virgin female of their own species. Ptilinus is sometimes terribly destructive to timber; and apparently the most remarkable instance on record of this undesirable characteristic is one given by West- ' wood, who states that a perfectly new bed-post (those were the days of the great four-posters that lumbered up our fathers' bed-chambers) was, in the space of three years, completely destroyed by countless numbers of these insects. But such depredations are necessarily becoming more and more things of the past, and in these days of iron bedsteads, &c., Ptilinus, and others of that ilk, must be beginning to find that they have fallen on evil times, and that the conditions of life are not nearly so favourable as they used to be in the happy days of old. I have found it also in a printing-office, where, in the abundance of wooden "plant" stored up, it must have discovered a perfect mine of wealth. Anobium domesticum is not the only representative of that genus in our household fauna ; another is A. pani- ceum, a shorter and broader insect of somewhat paler colour. It is almost omnivorous in its tastes, attacking any sort of vegetable substance that may fall in its way, though less of a wood-borer than its relative. Such things 14 OUR HOUSEHOLD INSECTS as dry bread, biscuits, rhubarb root, ginger, wafers, and even so unlikely a substance as Cayenne pepper, have been greedily devoured by it ; and it has also not un- frequently attacked ships' biscuits, riddling them through and through, and damaging them to such an extent as to render them quite unfit for human food. Nor does it make any difference it the vegetable matter is not in its primitive condition, but has had its character so much altered as is involved in having passed several times through the hands of the manufacturer : thus, paper will furnish it with an enjoyable meal, and books even yield it physical sustenance. A curious case of the latter is recorded of either this insect or some closely allied species : twenty-seven folio volumes in a public library were perforated in a straight line by one and the same insect, and so regular was the tunnel that a string could be passed through the whole length of it, and the entire set of books lifted up at once thereby a tolerably clear proof that the library, or, at any rate, that particular portion of it, could not have been in great request with human bookworms, or the insect ditto would scarcely have found its course so entirely unimpeded. Drawings and even paintings have also been destroyed by this insect, and on one occasion it invaded the sacred seats of learning and made away with some Arabic manuscripts in a library at Cambridge, and at another time wrought havoc in the herbarium of a botanist. The powerful jaws of the larva, too, are not deterred even by a thin coating of metal, for Westwood records having seen tinfoil perforated by it, no doubt for the purpose of pilfering some treasure contained beneath. So, while A. domesticum destroys chairs, tables, picture-frames, cupboards, floors, &c., and sometimes WOOD-CORING BEETLES 15 terrifies nervous old ladies by its ticking, its relative A. paniceum attacks the stores of comestibles, works of art, and literature of the dwelling, and between them they would, in the course of time, if unchecked, produce terrible ruin. When found in woodwork out of doors, the direct damage insects of this kind do by the actual excavation and devouring of the wood is not the only injury for which they are responsible; for damp air enters the substance of the wood through the burrows, and meet- ing with the excrement, which is stored in great quan- tities in the burrows, renders it a good basis for the growth of microscopic fungi, whereby the decay of the wood is accelerated. All the insects hitherto enumerated belong to the family Ptinidce, of which they constitute one section, the Anobiides, distinguished, at least so far as our house- feeders are concerned, by their more cylindrical form, compact make, and shorter legs. In the other section, the Ptinides, to which we now turn our attention, the shape is more globose, the antennae and legs much longer, and the thighs so much thickened at the outer extremities as to become club-like. From their shape it would be easy to conjecture what would be in accord- ance with facts, that they have less to do with cylin drical burrows than their companions who "swear by" Anobium. The typical genus of the Ptinides is Ptinus, and the commonest species of that genus P. far (Fig. 5). This is also a household insect, and is of somewhat varied habits. It well exemplifies a peculiarity exhibited with more or less distinctness in several species of this genus, viz., dis- similarity in shape between the sexes : the body of the male is almost cylindrical, but that of the female inflated 6 OUR HOUSEHOLD INSECTS or rounded at the sides, a feature which so alters her appearance that a novice would be certain to divorce her FIG. 5. Ptinus fur (A, male ; B, female). from her husband, and consider her a distinct species. It is a reddish-brown, hard insect, with two narrow and some- what indistinct bands of white hairs on the elytra ; the head is so much bent under the thorax that it cannot be seen from above, so that the insect appears as though it had been decapitated. The legs are long and straggling, notwithstanding which the creature is slow and heavy in its movements. The thorax is a good deal contracted behind, appearing as though it had been tied round tight while soft, and had hardened in that condition. By attending to these few points of distinction, there can scarcely be much difficulty in recognising a Ptinus. This insect is a great foe to Natural History collections, whether of animals or plants : and if by any chance it can manage to effect a surreptitious entrance into such, it does its best to execute the sentence " dust to dust " upon them. But its tastes are varied, and range from such excellent diet as the precious grain stored in granaries to the apparently less attractive nutriment WOOD-RORING BEETLES 17 furnished by the threadbare fabric of an old coat, the vegetable and the animal diet seeming equally suited to its taste, though it was at one time considered to be so largely an animal feeder as to have been called by De Geer vrillette carnassiere, "the carnivorous borer." Those who keep collections of foreign insects may sometimes have the privilege (?) of breeding (uninten- tionally) exotic species of Ptinus. Dried insects, when arriving from abroad, sometimes contain in their car- cases living larvae of Ptinidve, which fare sumptuously, though silently and unobserved, upon the " dried meat " by which they are surrounded a veritable "life in death." I remember on one occasion looking at a store box of exotic insects that had not been opened for some time, and being astonished at finding a colony of some dozen or so of a beautiful bright red Ptinus, prettily ornamented with snow-white spots, gaily disporting themselves amongst my stores, quite regardless of such insecticides as were present. I succeeded in tracing them to the huge carcase of a gigantic beetle that I had unfortunately introduced into the society without pre- viously submitting to quarantine, and in whose interior the larvae had evidently been holding carnival at the time of his introduction. The Ptini turned out to be a Polynesian species, which had thus completed their life cycle many thousands of miles from their birthplace. On their exclusion from their coleopterous host, they seemed to have decided on a change of diet, and so had calmly attacked the cork lining of the box, neatly excavating in it a series of hollows, to the extreme detriment of its appearance, at least from my point of view. A most extraordinary trio of beetles now calls for notice. They are closely allied to the genus Ptinus, B to 18 OUR HOUSEHOLD INSECTS and .belong to the same section of the family. They have very much the appearance of spiders, for which, indeed, they are often mistaken. The first is Niptus hololeucus (Fig. 6). It is a small beetle, completely covered with a yellow- ish silky down, and its resem- blance to a spider is produced by three peculiarities. A spider, which, be it remembered, is not an insect at all, but 'a member of u 'TTTrrrrrr a the class Arachnida, has only two y V apparent divisions to its body, FIG. 6.-Niptus hololeucus. the hindermost of which is usually highly convex and rounded at the sides, and it has also eight legs. Now, though Niptus has distinctly the usual three divisions of an insect's body head, thorax, and abdomen the first of these is so bent under the second that, as in Ptinus, it cannot be seen from above; and, in consequence, the body seems, like that of a spider, to be composed of only two parts. The elytra are very convex above, and much inflated and rounded at the sides, and as the line of their junction is completely obliterated, the abdomen acquires the globose and un- divided form of that of a spider. Again, the antennae, which are about equal in length to the legs, and, of course, on account of the bending of the head, appear to come from underneath as much as the legs themselves do, make up, with the usual six legs, a number of ap- pendages that may readily be taken for the eight legs of a spider. The imitation is so complete, that, when only casually seen, the beetle might easily deceive even those who are perfectly familiar with the difference be- tween an insect and a spider. When once one examines WOOD-BORING BEETLES 19 it closely, however, the apparent resemblances vanish, and the creature is easily seen to be a true insect, and is moreover found to be as hard -bodied as a Ptinus, instead of exhibiting the soft and yielding integument of a spider. It occurs commonly in houses, often in considerable numbers. It is not a wood-borer, but feeds on anything it can come across that is at all edible, and, in con- sequence, most frequents cupboards where stores of pro- visions are kept. It was once found in great numbers in a plate-cupboard, where it was said, though with what degree of justice it is very difficult to understand, to have done considerable damage to the silver stored there. It has no wings, and is therefore not much of a wanderer, so that when a colony has once established itself in any part of a house, the successive generations are likely to remain in those quarters as long as pro- visions last, unless forcibly ejected. It is probably not a truly indigenous insect, but, like many others, has been imported from abroad, so that, although not blessed with great powers of locomotion, it has yet been a con- siderable traveller. Under the microscope, the yellow clothing of Niptus is seen to be composed of two totally distinct elements. There are a number of longitudinal rows of long hairs or bristles, projecting considerably above the general surface, and pointing backwards ; and beneath these, closely covering the body, a quantity of tiny yellow scales, overlapping one .another. Each scale is bluntly pointed at the place of its attachment to the body, and at the outer extremity is usually produced into two long pointed projections at the sides, with a shorter one between them (Fig. 7). Not unfrequently the central process is also cleft. When the scales are removed, the 20 OUR HOUSEHOLD INSECTS body beneath is seen to be highly polished, and of a deep chestnut colour. To return to our spider-like trio : the first we have FIG. 7. Scales of Nip tus. FIG. 8. Mezium affine. already considered ; the second, Mezium affine (Fig. 8), is even more spider- like than its predecessor. Unlike Niptus, however, it is clothed with hairs only on the head and thorax. Its elytra are perfectly bare, of a chestnut-brown colour, brilliantly shining, and extremely globular, very much like what those of Niptus would be if denuded of their scales. The head and thorax are covered with yellowish- white hairs, so thickly disposed that one might imagine the creature was of an asth- matic temperament, and so needed to protect itself by wrapping its upper regions in a great woollen muffler or comforter. This is not nearly so common an insect as the last, but it is equally varied in its tastes. An old opera-hat, which had been laid aside for some time, once nourished a considerable colony; and it has also been found inside the carcase of another beetle, the greater part of whose contents its larva had devoured. The creature had passed through the whole .of its changes in these contracted quarters, the larva having formed there a silken cocoon intermixed with particles of its own excrement. The third member of our little party is Gibbium scotias (the hump-backed lover of darkness) (Fig. 9). It is much WOOD-BORING BEETLES 21 like Hezium, but more stumpy, and entirely destitute of hairs, except on its antennae and legs. It looks more like a great mite than a spider, and from its colour and rotundity has been fancifully com- pared, especially when tucking its legs underits body, to a drop of blood. FIG - 9--Gibbium scotias. At Newcastle this insect has been found in some numbers in a dry cupboard, where, it would seem, they had obtained a comfortable living from the wall- paper and the dried remains of the paste with which it had been hung. This latter is a very favourite repast with several small insects that are pests in Natural History collections; it is well, therefore, to take the precaution to mix a little corrosive sublimate with the paste used in preparing the mounting-boards for zoo- logical specimens, that by being thus poisoned, it may become safe from the attacks of the tiny depredators. GibHum has also been found amongst old hay, and on one occasion a heap of their carcases was discovered amongst a resinous substance in a vase obtained from a mummy at Thebes, but whether they were an ori- ginal embalmment or a subsequent invasion was not very clear. CHAPTEK II. CLUB-HORN BEETLES. WE now turn to another family of beetles, the Derme- stidcB, q, group of small extent, but of most destructive habits. ' One of them has rendered itself sufficiently obnoxious to have acquired a popular name, the " Bacon Beetle," a designation which indicates not a necessary association, but merely a casual one, which, however, has, more than any other, brought the insect under the notice and reprobation of human kind. In scientific language it is still called by the name under which the great Linne wrote of it in his " Systema Naturae," viz., Dermestes lardarius, the second word of which is an almost literal translation of the popular name. The gene- ric title Dermestes is from the Greek derma, a skin, and in- dicates that the tastes of the insect lie, not only in the direction of fat bacon, but equally in that of tough leather. It is a parallel -sided convex rather elongate insect, about one-fourth inch long (Fig. 10), and may be at once recognised by the yellowish-grey band which sweeps right across the elytra, occupying almost the whole of FIG. 10. Dermestes'lardarius. CLUB-HORN BEETLES 23 their basal half (i.e., the part next the thorax), in sharp contrast to the black of the remainder of the body, both before and behind. The two colours meet abruptly in a well-defined, somewhat wavy boundary line, running across from side to side. In the present order it very frequently happens that, as we have already seen in Niptus, the colours that appear on the surface are not ingrained into the skin of the insect itself, but are produced by hairs or scales, with which it is more or less thickly coated ; and it is not until these have been removed that the true colours of the body, which do not necessarily correspond with the superficial orna- mentation, can be clearly ascertained. The present insect is covered tolerably thickly with hairs, and the parts that are superficially black are also of that colour when denuded of their covering, but under the pale patch the elytra are of a very deep reddish-brown. The head is of small dimensions, and, when the insect is at rest, is carried bent down beneath the thorax, a position from which, in a defunct individual, the cole- opterist who desires all parts of his specimens to be properly displayed, finds it no easy matter to coax it out. The antennae are of the type known as clubbed, a feature which indicates that the insect belongs to that large section of the beetle order called Clavicornia, or Club -horns, a group containing about 600 British species, a good many of which are feeders upon carrion and the dried carcases of other animals. A clubbed antenna is usually almost abnormally short, and may be at once distinguished by the fact that the terminal joints, two, three, four, or five in number, are much broader than the rest. It is surprising how many varieties this very simple peculiarity is capable of, and these variations are of much importance in the 24 OUR HOUSEHOLD INSECTS systematic arrangement of the insects. In our present species the club consists of three flattened joints, broadened inwardly only, whereby it acquires a one- sided appearance. The legs are of moderate length, and are packed up under the body when their owner counterfeits death, as it very readily does on the slightest alarm, being, as well becomes so inveterate a pilferer, of timid and retir- ing habits. But this folding up is not so perfectly carried out as in many other insects, for the last section of the limbs, viz., the five- jointed tarsus, or foot, is not folded back upon the preceding part, or tibia, but simply brought up so as to make an angle with them. - t . The larva of Dermestes is something like a very hairy caterpillar, and is no connection of those lively maggots that also infest bacon, and whose acrobatic feats have earned for them the name of " jumpers." It casts its skin several times in the course of its life, and on account of the multitude of hairs (which are shed with the skin and renewed each time), the rejected vestment does not shrivel up, but retains the form of the larva, a very substantial ghost of its former self. We possess five British species of this genus, all of which are essentially devourers of skins and dried carcases; in fact, they are the jackals of the flesh flies, coming round when the maggots of the latter have finished up all the soft and juicy parts of a fresh carcase, and clearing off the hard and dry remnants of the skin, tendons, ligaments, &c., which their predecessors have left untouched. This is their natural function in the economy of nature, and when man also accumulates stores of dried meats, skins, feathers, horns, and hoofs, it is not to be wondered at that they forsake the scanty and precarious provisions of dame Nature, and invade CLUB-HORN BEETLES 25 his precincts who has so thoughtfully laid up such grand stores for them. Some years ago, D. vulpinus, a black species with a white patch on each side of the thorax, swarmed to such a degree and was so destructive in large skin ware- houses in London as to bring forth the handsome offer of ^"20,000 for an available remedy. But satisfactory remedies against the ravages of insects are usually diffi- cult to discover, and difficult also to apply; and it is not altogether surprising that even so tempting an offer failed to secure the desired result. The curators of museums, too, are likely to have their peace of mind affected by the ravages of Dermestes. The larvae are by no means parti- cular as to the class to which a preserved animal belongs, and so birds, beasts, and fishes, crabs, insects, and spiders may any or all fall before their jaws. Sometimes they will attack a skin by nibbling away at the roots of the hair or feathers, and so make a nice clean shave of the whole affair ; occasionally they will forsake an animal for a vegetable diet. Cork is a substance much favoured with their attentions, and an account has been placed on record of the destruction of a whole ship's cargo of this material by vast numbers of them. On another occa- sion they actually abandoned some tempting skins on which they had been feasting for a set of corks that had been introduced into their quarters. Nor is the house- wife exempt from anxiety on the score of Dermestes. Not only flitches of bacon, but even the meat in larders, and the bladders covering the tops of jam-pots, have on occasions yielded to their rapacity; books and papers, too, are not safe, and, strangest of all, they have sometimes actually imitated the example of Anobium, and bored into wood, feeding on the timber as they advanced. 26 OUR HOUSEHOLD INSECTS But the most repulsive charge against them is that of anthropophagy. Some years ago, some Egyptian mum- mies were discovered, which, perhaps through straitened circumstances in the family to which they belonged, or through the shiftiness of some dishonest firm of embalmers, had evidently been prepared with less care than was usually expended on such objects. On being unswathed, the bodies were found to be pierced in some places by an insect identical with the London warehouse pest above referred to, viz., D. vulpinus, some examples of which had worked their way through two or three folds of the mummy-cloth and there perished. The bodies, on being opened, were found to contain thou- sands of the larvae, together with many more of the perfect beetles of course, all mummified and saved from decay by the same drugs as had preserved the mummy itself. From the facts that death had overtaken the larvae in the fulness of their powers, that only a few beetles had escaped from the body, and that these had not been able to work their way out completely, it is manifest that they must have commenced their attacks during the preliminary processes of embalmment, when evidently the body had been somewhat neglected, and that most of them had been killed by the later stages of the operation, a few only surviving its completion, and they were without strength sufficient to eat their way completely through the investing mass into daylight. The Dermestes were accompanied by another beetle, a bright blue species called Corynetes violaceus, which also is a common British insect, and a devourer of carrion and skins, though belonging to a different family. It was well for the feelings of the survivors and owners of the precious relics that all these insects perished where and when they did ; for think what a shock it would CLUB-HORN BEETLES 27 have given to the family to see a host of beetles come trooping out of the corpse of their respected relative, the integrity of whose remains had been an object of their pious care ! In consequence of the great amount of preservatives used, the bodies themselves, when once properly prepared, would probably be exempt from in- sect attack, but not so the wooden cases in which they reposed, which could easily be, and were, perforated by wood-borers such as AnoMwn; and, to judge from some in the British Museum, the ancient Egyptian may have had to look as sharply after the coffins of his grand- fathers as the modern Englishman after his chairs and tables, to prevent them from becoming worm-eaten. Belonging to the same family as the Bacon Beetles are a few other insects that sometimes augment our household fauna. One of these, called Attagenus pellio (Fig. n), is very much like a small Dermestes, both in form and in life history. It is a black insect, about one-fifth inch long, with a small but bright white spot (composed of hairs) nearly in the centre of each elytron, and also three similar but less brilliant ones on the hinder edge of the thorax, of Fia - which the centre is the most conspicuous. There is also usually a slight indication of a second and much smaller spot on each elytron, placed nearer the thorax and more at the side than the two bright silver points before alluded to. Of course, all these spots, being simply composed of hairs, easily become obliterated by the wear and tear of life, friction against obstacles causing their speedy abrasion. This insect is of very similar habits to a Dermestes, and in domiciling itself with us may generally be regarded 28 OUR HOUSEHOLD INSECTS #s being engaged in fur-hunting. The name "pellio," which is Latin for a " furrier " a preserver of and dealer in furs is somewhat contradictorily given to this destroyer of such wares. Linne, who says that it will sometimes entirely strip a fur garment of its hair, accuses it also of attacking the household stores of food, and, besides this, it is occasionally a nuisance in Natural History collections, and has sometimes eaten holes in carpets. Its larva is closely covered with reddish-brown hairs, which give it a shining silky appearance, and it has a long brush of hairs at the tail. Our la,4t representative of this family is a much smaller insect, which has nevertheless rendered itself notorious by its invasion of museums a fact, the memory of which has been perpetuated in the second half of its name, Antlirenus musceorum (Fig. 12). It is a short oval insect, about one-twelfth of an inch long, prettily sprinkled with variegated scales, FIG. 12. Anthrenus which give it a mottled appearance, the musseorum, as it . : A appears when pale ones on the elytra being distributed feigning death. . / fc in three more or less distinct, irregular, transverse bands. The scales are pretty objects for the microscope. They are triangular in shape, and, of course, attached by the apex of the triangle, and their principal colours a very deep brown and pale yellowish-white. On their removal, the whole insect appears black. In the power of feigning death, by bending the head under and packing up the legs, this insect is quite equal to the most obstinate of its allies. The larva is hairy, like that of Dermestes, but, of course, much smaller. Its hairs are in bundles, and at its tail are a pair of tufts of larger size ; when it is at rest these two are laid along the back, but when disturbed it erects them/^and CLUB-HORN BEETLES 29 spreads them out like a couple of shuttlecocks. On account of its hairy nature it is a very slippery creature, and this, combined with its small size, makes it a diffi- cult captive to hold, and enables it easily to slip between the fingers. It is nearly a year in attaining its full size, though not equally vigorous during the whole time; it is much more active in summer than in winter, and feeds chiefly during the warm weather. At length, after several moults, the time for pupation arrives ; the last larval skin, however, is not thrown off as its predeces- sors have been, but, a slit having been made down the back, the insect becomes a chrysalis inside the hairy shroud, from which, on attaining its final form, it makes its exit at the aforementioned slit, leaving its last two coverings one inside the other. Five species of Anthrenus are known as British, and it is curious that the perfect insects frequent living flowers, especially those of the UmbelliferEe, in which they may sometimes be found gregariously. The larva of A. musceorum, however, feeds upon skins, hairs, feathers, and other dried remains of animals, though it is difficult to understand what temptation there can be for an insect's taste to oscillate between fragrant and aromatic flowers on the one hand and evil-flavoured and malodorous animal remains on the other. Apparently, however, it is not much affected by smells, for the powerful odour of camphor, which is destructive to many insects, seems not to incommode it at all; and, there- fore, the keeper of natural curiosities will not permit himself to be deluded into the persuasion that all must necessarily be right with his collections if he has but applied camphor to them after the usual manner. This is no effectual preservative against Anthrenus; in fact, the wretched little creature has actually been found 30 OUR HOUSEHOLD INSECTS snugly nestling under the very camphor that had been inserted for its destruction, in utter scorn of all such precautions. Its smaller size, too, renders it a more difficult enemy to guard against than Dermestes, as it can both enter through smaller interstices and is less conspicuous, though not less destructive when once an entrance has been effected. Still keeping to the great section of the Club-horns, we come now to a minute insect called Mycetoea hirta (Fig. 13). This little creature has been at times bandied about from one family to another, and its true location is difficult to determine. It is only one -sixteenth inch long, of a pale chestnut colour, with rows of large and deep (comparatively) pits or " punctures " on the elytra, (the word FIG. 13. Mycetsea punctures, as used in entomology, does not imply complete perforation, but merely indicates sudden and minute depressions, usually circular in form) ; the whole surface of the insect is beset somewhat scantily with long coarse hairs, which stand out like chevaux-de-frise all over its body, and have gained for it the name of hirta, "hairy." The thorax seems as though its lateral edges had been turned up, folded back, and fastened down along the sides of the dorsal surface, somewhat as the edge of a piece of needlework is folded over to make a "hem." It is obvious, when one remembers the small size of the insect, that none of these peculiarities can be seen with- out the aid of a lens. This little insect is an inhabitant of old wine-cellars, where it feeds upon the fungoid incrustations on the walls, and, according to some, also attacks the corks of the bottles. Some people, however,. CLUB-HORN BEETLES 31 believe this last charge to be unsubstantiated, consider- ing the real damage to have been done by other insects found in the cellars, in which case Mycetcea has got into ill repute through association with evil companions. Its larva is a whitish fleshy grub, with six small legs in front. In its cellar experiences, this insect is often accom- panied by other minute beetles, especially certain tiny yellowish-brown ones of the genus Cryptophagus, a word derived from the Greek, and signifying an "eater in concealment." This is a large genus, and a very puzzling one, on account of the great similarity of the species. They may easily be distinguished from other small, similarly coloured beetles by the fact that the lateral edges of the thorax are produced into tooth-like projections, which differ in shape and position in the different species, but are almost characteristic of the genus as a whole. CHAPTEE III. CELLAR BEETLES AND MEAL WORMS. THE beetles whose ravages and life history have already occupie4 our attention illustrate very well two of the great primary divisions of the Coleoptera, viz., the Tere- dilia or wood-borers, containing the Death Watch and its allies, which are all summed up in a single small family, and the Clavicornia or Club-horns, to which the Bacon Beetle and its skin-devouring relatives are referable. We thus see that in each section, out of some hundreds of species of more or less similar structure, only a very small proportion, and those almost entirely confined to a single family in each case, bring themselves into collision with human household interests. And in the same way, to get our next illustrations, we must go to another great primary section of the order, and select a few species therefrom. This section is called the Heteromera, a word which, being literally translated from the Greek, means "different joints, 7 and is given in reference to a peculiarity by which these insects are sharply distinguished from most of those already referred to, viz., that while the tarsi, or feet, of the first two pairs of legs consist of five little joints succeeding one another in longitudinal row, those of the hind pair have only four such joints, our preceding examples, except the little oddity Mycetcea, having been furnished with five on all their limbs. 32 CELLAR BEETLES AND MEAL WORMS 33 The Heteromera are a remarkable set of insects, more fully represented in tropical countries than in our own islands. We possess less than 120 species, and these do not all rightfully belong to us ; but even this small number includes insects of such diverse habits and struc- ture as to necessitate their subdivision into nearly sixty genera. The economy of some, too such as the fami- liar oil-beetle is more wonderful than that of any other Coleopteron whatever. Our first example from this group is the insect known to science as Blaps mucronata (Fig. 14), and popularly FIG. 14. Blaps mucronata. A, side view of elytra. called the "Churchyard Beetle" and "Cellar Beetle." It is utterly unlike any other British insect, except the other two members of its own genus, and these it resembles so closely as to be with difficulty distinguish- able from them. It is a dull-black creature, nearly an inch in length, with long, straggling legs, and without wings, though the wing-covers, or elytra, are even more largely developed than usual. These cannot, however, be opened, and are, indeed, actually fastened together " soldered " is the technical term along their central c 34 OUR HOUSEHOLD INSECTS line of junction, thus forming a flattened arch over the body. It shows no trace of ornamentation on any part of its body, not even the customary longitudinal furrows and rows of punctures so characteristic of beetles ; and at first sight the integument seems to be perfectly smooth. Examination with a lens, however, reveals a minute and indistinct, irregularly scattered punctuation. The body is broadest a little behind the middle, and at the tail the elytra, instead of terminating in a smooth, evenly rounded edge, are each produced at the tip into a blunt projection, curled upwards (Fig. 14, A). The name mucro- nata, from the Latin mucro, a spear point, refers to this odd little tail, which is, nevertheless, not confined to this species, but is represented in one form or other through- out the genus. Turning next to the organs of sense, we find another striking peculiarity in the eyes : instead of forming projecting rounded masses, as is usually the case, they consist of two long, narrow, almost kidney- shaped strips, just behind the antennae, and not raised above the general surface. This want of prominence of the visual organs finds its explanation in the darkling habits of the creature. Finally, the last four joints of the antennae are like round black beads. Blaps has really very little to recommend it. Its dull sombre aspect is the reverse of attractive, and agrees well with the retirement and obscurity of its life. Clad so completely in the deepest of mourning, it could not be let alone by superstition, and has therefore been regarded with terror as an ally of the powers of dark- ness, and an associate of death a creature whose natural abode could be none other than a charnel-house. Ideas so fostered found apparent support in the repulsive odour it continually emits, resembling that of putrid flesh, and CELLAR BEETLES AND MEAL WORMS 35 in its not unfrequent occurrence in churchyards. Its disgusting odour is produced by the vaporisation of a fluid found in two oblong vesicles near the tail. An unusual length of legs is generally an indica- tion of agility, but not so with Blaps, which is a very tortoise in speed. It leisurely lifts one leg after the other, cautiously bringing them again to the ground, as though its vitality were well-nigh exhausted, and these were its last feeble efforts before giving up the ghost. Nothing could be farther from the truth, however, for its stock of vitality is extraordinary, and enables it to survive dangers and difficulties which would speedily be fatal to less hardy creatures. About a century and a half ago, when entomology was hardly yet a science, and the means of destruction of insect life not so varied or efficacious as at present, a struggle, so celebrated as to have been thought worthy of permanent record in the '' Transactions of the Royal Society," took place between a Blaps and an entomologist. The latter made no less than four different attempts at the execution of the former, by immersing it in spirits of wine for periods of increasing length, the last extending over some twelve hours. On each occasion life appeared to be extinct, but each time also, on being removed from the fluid, the apparent corpse became reanimated, and the victim of alcoholic excess entered on a new lease of life, till at last the sentence was remitted, and the insect lived with its captor unmolested for three years afterwards, and even then the record of its experiences was brought to a close, not by its own decease, but by the carelessness of a domestic, who allowed it to escape. This insect is often found in cellars, stables, and out- houses, dark and damp spots being especially congenial to its tastes. It shuns the light of day, and is chiefly 36 OUR HOUSEHOLD INSECTS nocturnal in habits. Though so disgusting in smell, it found a place in the Materia Medica of the Romans, being recommended by Pliny as an infallible remedy in the case of ulcers which would yield to no milder treatment. The larva is a long narrow creature, with six short legs in front, very similar to an ordinary meal worm, to which, indeed, it is not very distantly related. It is of a pale, yellowish- white colour, and not hairy, like those of the Dermestidce. This, therefore, is the third type of larv^, we have met with : the first, of the Ptinidce, plump, fleshy, soft, pale, and curved ; the second, of the Dermestidce, densely hairy, like moths' caterpillars ; and the third, that of Slaps, long, narrow, and smooth. The larva of an allied species has been turned to account by the women of Egypt, who, following the precepts of " insectarianism," are said to make a savoury dish of the grub by roasting it and serving in butter, partaking of it with a view to the cultivation of embonpoint. In order to find the other household members of the Heteromera, we must leave for a time the cellars in which we were hunting for our first representative of the group the foul churchyard beetle and visit loca- lities of an altogether different description, viz., bakers' shops, bakehouses, flour-mills, and granaries. Farina- ceous substances, such as wheat, barley, maize, meal, flour, bread, cakes, &c., are specially liable to the attacks of various species of beetles belonging, curiously enough, to several totally distinct sections of the order. In stores of corn in granaries no less than eighteen species of beetles have been found amongst the refuse, though it is probable that several of these were there, not to eat the grain themselves, but to prey upon such of their CELLAR BEETLES AND MEAL WORMS 37 associates as were addicted to that practice. Still, it is certain that there is a gang of nearly a dozen species that will engage in this work of destruction whenever they can get a chance, and the ringleaders are those two great sinners, the corn and rice weevils. As these, however, belong to the granary rather than to the dwelling-house, we need not stay to describe them here. Our old friend, the omnivorous Niptus, sometimes joins the ranks of these "corn-lovers," and Dr. Power records having found it in hundreds in a quantity of meal, which he transferred to a closely stoppered bottle, where, notwithstanding that the bottle was never opened, the insects continued to breed for three years, though in gradually decreasing numbers. But our concern at present is with the Heteromerous members of this gang of freebooters. They are chiefly of small size, and none of them equal Blaps in stature. By far the largest are those whose larvae constitute the well-known " meal worms," belonging to the genus Tenebrio, from which the whole family is named the TenebrionidcB. The meal worms themselves we reserve for a future notice, and turn our atten- tion at present to the smaller species. First, we have two very closely allied insects, called Tribolium ferrugineum and T. confusum, the former of which (Fig. 15) is much the commoner. They occupy a position very inferior to the corn-weevils in point of destructive- FIG. 15. Tribolium ferrugineum. ness, but still they are an enemy not to be despised. They are both small, dark, reddish-brown insects a colour referred to in the name ferrugineum, " rusty " of insignificant appearance, and, like several others of the group, do not rightfully belong to the 38 OUR HOUSEHOLD INSECTS British fauna, having been introduced here with foreign merchandise. They have, however, established them- selves, at least under the shelter of human roofs, where they will breed freely, and therefore, though they do not yet appear to have become naturalised in the truly wild condition, they are usually included in lists of British insects. They are so much alike that to a casual observer they would appear identical. By a very close and careful comparison under the microscope, minute points of dif- ference in the antennae, thorax, and punctuation can be made out, but these are of too minute and technical a character to be rendered intelligible here. In the name confusum, the " confused," given to the second species, we have an indication of the difficulty that attends their separation, and of the probability of their being con- founded together. There is one peculiarity, however, possessed in common by these insects and their allies which is worth notice; it is that the eyes, which look like piles of tiny, polished, black beads, are much encroached upon by a projecting ridge in front of the head, which is produced backwards in such a way as to appear to have grown partially across the eyes, almost entirely dividing each mass into two unequal parts, one above, the other beneath. The larvae of these insects are tolerably active, some- what hairy creatures, with six short legs in front. In common with larvae generally, they change their skin several times, each time making their exit from the slough through a slit along the back of the neck, drag- ging out therefrom, first the segments that afterwards become the thorax, then the head and legs, and finally the abdomen. Previously to assuming the pupal form, they become CELLAR BEETLES AND MEAL WORMS 39 restless, and search about for a suitable place of lodg- ment; having found one to its taste, the grub arches its back and divests itself of its last larval skin, and then passes very rapidly through the resting-stage of pupadom, appearing in an incredibly short time as a perfect insect, ready again to take part in the activities of life. At first it is pale, and the elytra are so trans- parent that the body can be seen through them ; after a few days, however, they acquire their characteristic ferruginous colour and opacity. The pupa shows dis- tinctly all the parts of the perfect insect, the head, wings, and legs being bent down underneath the body. These insects do not confine their attentions to farina- ceous substances ; they are also animal feeders, and are amongst the enemies to be dreaded by the keeper of collections of natural objects ; their larvae will excavate the carcase of a dried insect as effectually as will those of Dermestes or Anthrenus. Another bakehouse insect is Gnathocerus cornutus, which is identical in colour with TriboUum, and very similar in shape, but somewhat larger. Its names, Ghiath- ocerus, "jaw-horn," and cornutus, "horned," both refer to a peculiarity of the male only, by which that sex can be easily distinguished from all other members of this group. The mandibles, i.e., the biting jaws, are each in the form of a long horn, the pair of which, project- iTiw wmei'rlaT>ahlv in ffrmt FIG. 16. Head of Gnathocerus ing considerably in tront cornutus (much magnified). of the head, and curling upwards, give the insect a most formidable aspect. The head (Fig. 16) is altogether an odd-looking object, 40 OUR HOUSEHOLD INSECTS for, besides these mandibular horns, there are two blunt horns on the forehead, and the ridge that almost divides the eyes is produced into a kind of flap or scoop on each side. By these remarkable structures we are reminded of what seems almost like a law in the insect world, viz., that of all the different parts that make up the whole organism of a typical insect there are some, such, for example, as the legs, that preserve a very great uni- formity of type throughout the class, varying in the differen^ groups, and through the thousands upon thou- sands of species, only within comparatively narrow limits, while others seem possessed of much greater plasticity, so to speak, and run off occasionally into such eccen- tricities, extravagances, and apparent monstrosities, that it seems as though there were no limit to the modifica- tions of which they are capable. Perhaps the best illustrations of this are to be found in the thorax and antennae, in both of which most marvellous and unex- pected developments, both in shape and size, are to be met with. And in our present insect we see the head and mandibles partaking of this same tendency to fan- tastical modification, a tendency which, so far as man- dibles are concerned, is manifested in a most remarkable degree also in the stag-beetle, the " horns " of which are really its jaws. And in that case, too, as in the present, it is in the male sex that the structural peculiarity is found. We conclude our notice of the family Tenebrionidce with the creatures called " meal worms," which are the larvae of two species of beetles, Tenebrio molitor and T. obscurus. Both larvae and perfect insects are found in granaries, flour-mills, and bakehouses, where they CELLAR BEETLES AND MEAL WORMS 41 sometimes do much damage to meal, bran, and flour. The larvae are much more familiar objects than the imagos, though probably the reverse is the case with the rest of the family. They are used as food for cer- tain singing- birds, and other insectivorous creatures, and hence are bred in large numbers by bird-fanciers. This may readily be done by keeping them in bran, when they will propagate themselves freely. The word Tenebrio is Latin for a night-walker, or lover of dark- ness, and, so far as the mere meaning is concerned, the name would be just as applicable to the rest of the family as to the present insects, the whole set being devotees of obscurity. Molitor is Latin for grinder of corn, and obscurus finds its explanation in the dull appearance of the second species. T. molitor (Fig. 17) is a narrow, parallel-sided beetle, a little over half-an-inch in length. Above, it is almost B'IG. 17.- A, Tenebrio molitor ; B, larva of ditto (natural size) ; C, pupa of ditto. black, the faintest possible tinge of a dark brown-red preventing it from being quite so ; or perhaps it might be more correctly described as deep brown-red, so deep as to appear almost black. Beneath and in the legs the lighter colour is much more apparent. It is slightly shiny, but only just sufficiently so to be redeemed from 42 OUR HOUSEHOLD INSECTS the utter dulness and dinginess which characterise its relative, T. obscurus. Down the elytra run the inevitable parallel furrows, sixteen in number, not deep, but dis- tinct enough to form a little " set-off " to the otherwise uninteresting appearance. The front of the head forms a ridge, which, as in some other species previously re- ferred to, encroaches considerably on the eyes. The legs are rather short, and the antennae are inelegant, thick, and stumpy. Unlike Slaps it is furnished with wings, and therefore, of course, the elytra are not soldered together. T. obscurus is a trifle larger than T. molitor, perfectly dull black above, without a trace of the red-brown tint, which, however, appears again on the under side ; in other respects it is almost the exact counterpart of its slightly less inelegant congener. Such are the parents of our meal worms. The "worms" themselves (Fig. 17, B) are as different as can well be imagined long, narrow, cylindrical, caterpillar-like creatures, consisting of a head and twelve similar and perfectly distinct segments. The colour is pale yellow, shading off into yellowish- brown towards the head and tail. Each segment at its hinder edge carries a rather broad band, and at its front edge an exceedingly narrow one, of the darker colour, so that the body is adorned with a series of double rings encircling it at intervals along its length. The last segment is rounded behind, and terminates on its upper surface in either one or two small black curved hooks. The head is furnished with a pair of not very large, but nevertheless strong, dark brown jaws, which, in repose, close in between the upper and lower lips, so that only their outer edges are seen. There is also a pair of tiny antennae. CELLAR BEETLES AND MEAL WORMS 43 Under the three segments immediately succeeding the head are three pairs of short legs, each terminating in a sharp curved claw. By means of these the " worm " is able to progress at a tolerably rapid rate, provided there are sufficient irregularities in the surface to afford foothold to its tiny claws ; but if transferred to a polished surface it presents a ludicrous spectacle; the front part of the body makes mighty efforts, struggling vigorously with its legs, and twisting itself from side to side, in vain endeavours to stir the inert mass of legless body which acts like a drag behind. The two legs in each pair are moved forward simultaneously, and the order of movement, which is not always quite uniform, and is extremely difficult to follow, appears generally to be first the front pair, then the third, and lastly the second. As the insect walks along, that part of the body immediately over the legs is, of course, somewhat raised, but the head is kept near the ground, so that it may feel its way with vibrating antennae and palpi. When walking slowly, or endeavouring to extricate itself from a difficult position, it also makes use of a pair of fleshy tubercles underneath the front part of the terminal segment, thereby either helping the hinder part of the body forward, or acquiring leverage for the proper action of the legs. But when trotting briskly along there seems to be no necessity to call these tubercles into play, and the hinder part of the body therefore simply trails helplessly over the ground. When fully grown, the larva is nearly double as long as the beetle it produces, but what the latter loses in length it gains in breadth, as it is fully twice as broad as its ancestral worm. Having spent some months in devouring farinaceous substances, and changed its skin several times during that period, the " worm " enters 44 OUR HOUSEHOLD INSECTS its penultimate stage by another moult, but without forming any cocoon. It is now shorter and broader (Fig 17, c), no longer a roving pirate, but a restful helpless mummy, giving prophetic indications of its future destiny in its altered form a beetle to all in- tents and purposes, but a caged and helpless one. After a few weeks the needful changes in its internal economy have been accomplished; it throws off its last skin, and appears a fully developed winged beetle, at first soft and red, but destined soon to acquire its natural firmness vand pitchy colour. Previous to every moult, the meal worm acquires a bloated appearance, and becomes inactive for a time, lying on its side in a curved position, and resenting all interference with petulant twitchings of its form. These meal worms will attack bread, cakes, &c., as well as uncooked cereals, and they have also been accused of devouring corks. When we remember how many different species of "corn-loving" beetles occur in our corn-stores, and how excessively abundant some of them are, we are forced to the conclusion that many must often be ground up with the flour, and that we, therefore, sometimes get our bread adulterated with pulverised beetles, and un- consciously become " insectarians " for the nonce. But "what the eye doth not see, the heart does not grieve over," and possibly we may not really be any the worse for this slight admixture of animal matter with our farinaceous diet, though there are not wanting those who have thought otherwise. Many of these " corn- lovers" are Heteromera, as we have seen, and to this section belongs also the blister-beetle, renowned in medicine, and no very distant connection of our Tene- brios. Moreover, a Brazilian species of Tenebrio is CELLAR BEETLES AND MEAL WORMS 45 known to eject from its body a caustic secretion, and some other allied insects cover themselves with a similar substance. Now, if our mealworms, &c., have properties at all analogous to those of Spanish Fly, this internal application of cantharides, even in homoeopathic doses, might not, perhaps, be altogether desirable. Some, too, have supposed! the celebrated corn-weevils to be prejudicial to health when in a comminuted state. Flour is not the only article of food that is liable to adulteration in this way. Curtis, in his " Farm Insects," has the following uncomfortable and suggestive passage : "I have known bushels of cocoa-nuts (i.e., of course, cacao) which were, every one, worm-eaten and full of maggots, with their webs, excrement, cast-off skins, pupae, and cocoons all ground down to make chocolate, flavoured, 'I suppose, with Vanilla." CHAPTEE IV. LONGHORNS AND PREY-HUNTERS. ONE of the finest, though at the same time most destruc- tive, divisions of the beetle order is that called Longi- cornia, or Longhorns. The beetles are many of them remarkably handsome, and of considerable size, and are readily distinguished by the great length of their antennae, which, in some cases, many times exceed even that of the body itself. These insects, in their larval condition, burrow into the solid wood of timber trees, where they live, often from three to five years, devouring the heart wood, and utterly ruining the timber by exca- vating through it in various directions neatly cut galleries, which, commencing on the outside in a small and scarcely noticeable opening, constantly increase in diameter with the growth of the larva. As a consequence of their longevity and the seclusion of their life, it not unfrequently happens that when an affected tree is cut down, and has been sawn up into planks, the latter contain some of the immature larvae, which escape notice through their burrows not having been sawn through, and thus get conveyed into timber- yards, and even used in building construction, before their occupants have had time to complete the necessary arrangements for making their debut in beetle society. After a while, however, this important era in the life of the insects arrives, and the beetles make their exit from 4 6 LONGHORNS AND PREY-HUNTERS 47 their burrows, only, however, to find themselves far away from their native forests, strangers in a strange land, and suddenly introduced into a human society, which is as astonished to receive them as they are to find themselves in its presence. In this way many fine exotic Longicorns have been captured alive in different parts of England, and this, too, is the explanation of the not unfrequent occurrence of the Longicorn beetle called the "timberman" in mines. They have been introduced in the larval condition in the timbers used in roofing and supporting the passages, and have some- times established themselves and bred there. Various forest trees are liable to the attacks of Longicorn beetles, but, of course, it is those that burrow in fir-wood that are chiefly imported into this country. So, then, there are some of these Longicorns that may every now and then be expected to turn up in houses. Our British species are few in number, and, as a rule, not common ; still, I have received one of our smallest in considerable numbers from two different houses. It is a quaint little brown beetle, which is said to be partial to old wood-work, and is called Gracilia pygmcea (Fig. 18). It is a narrow linear insect, with antennae only a little longer than the body, the length being produced, as in all this section, not by a mul- tiplication of the joints, but ,,-,..,.., ,, .. FIG. 18. Gracilia pygmsea. by their individual elongation. It is remarkable for the disproportionate size of the thorax, which, with the head, occupies about one-third the length of the whole body, and for the great breadth 48 OUR HOUSEHOLD INSECTS of the thighs at their outer extremity. The antennae, as might be expected, are very liable to damage, and as the insects are pugnacious, if several of them are confined together, they are sure to fight, and, as a consequence, a great mutilation of antennae and legs ensues, the battle- field being strewn with the fragments. It has also been found in large numbers burrowing in the twigs of a hamper, which, small though they are, afford plenty of scope for our pigmy beetle. Baskets form, in one way or other, an easy means of transfer- ence for insects from one country to another. Many continental species are brought over with fruit and vegetables, and the Borough Market, in London, is quite noted for the number of such insects that have been found alive there. About twelve years ago, a French Longicorn was introduced in large numbers by means of a basket ; some escaped, and were afterwards found in the open, when it seemed as though a new British beetle had been discovered. Fortunately, how- ever, their captor was a coleopterist of repute, and he, by means of careful observation and inquiry, managed to elucidate their history. The account is best given in his own words : " During the July of 1880, one of my servants brought me two specimens taken in the garden at the back of the house (the only two specimens then noticed). Last July, however (1881), two or three more were captured, and a day or two after they called my attention to the fact that numbers (dozens, in fact) were creeping upon the floor in the scullery ; upon examina- tion, I traced them to an old basket used for potatoes, and generally kept under the slopstone, and consequently moderately damp; in this they showed their presence by numerous small round holes, about the size of a pin's head. The basket, on being submitted to a professional LONGHORNS AND PREY-HUNTERS 49 basket-maker, was pronounced to be 'of French make, from Dutch willows.'" They had, therefore, evidently established themselves in the basket while in their native country, and subsequently accompanied it across the Channel, when it was used for the transport of vegetables. The larva of a much larger beetle, called Hylotrupes lajulus (Fig. 19), has sometimes done considerable damage to the rafters of houses, not only perforating the wood, but even gnawing its way through sheets of lead with which the rafters were covered. Kirby states that Sir Joseph Banks once gave him a specimen of sheet-lead, which, though only measuring eight inches by four, was pierced with twelve oval _ !l