NRLF B UNIVERSITY OF CALIFORNIA. GIFT OK /2 .JL- d/\ ..Co <^z^ oZ/ .<&^ . , f)S^ f wed i8gq Accession No. 76" 8 4^ \$ ^ Cla&s No. BIO BRARY t*vwJvUywA -tAxJu A. AUSTRALASIAN ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE. SYDNEY SESSION, 1898. Sljort Dichotomous Key to tlje Ijitherto kqown Species of Eucalyptus, BY J. G. LUEHMANN, F.L.S. (Curator, National Herbarium, Melbourne). Head before the Australasian Association for the Advancement of Science, January, 1898. 3253? BIOLOGY LIBRARY G I UJN I V JbJbibjL 1 A SHORT DICHOTOMOUS KEY TO THE HITHERTO KNOWN SPECIES OF EUCALYPTUS. By J. G. LUEHMANN, F.L.S. (Curator, National Herbarium, Melbourne.) (Read before the Australasian Association for the Advancement, of Science, Tuesday, January 11, 1898.) THE scheme herewith laid before the members of the Association, to classify the species of the genus Eucalyptus according to the fruits, is not, I may state at the outset, meant to supersede the excellent anther-system introduced by Bentharn ; the latter being in my opinion the most reliable which, with our present know- ledge, can be devised. Frequently, however, when specimens are gathered, expanded flowers, or even well-advanced buds, are not available, while nearly every adult tree bears fruits as well as young flower-buds, and in most cases, though not in all, the species can by their aid and that of the leaves be determined with toler- able accuracy. The present arrangement should, therefore, be looked upon as devised to act as an auxiliary guide only, without any full descriptions, and is for this reason submitted in the form of a key. The primary character chosen is that of the fruit-valves, whether quite enclosed or whether the points protrude beyond the rim, or whether the top of the fruit is convex with every part raised above the rim ; secondarily, the shape and size .of the fruit are taken into consideration. De Candolle's classification, based on the shape of the operculum, is relied upon for further sectional divisions. While the majority of the species are without difficulty assigned to their respective divisions, there are others which form a transit and, in these cases doubts will arise, especially when we consider their remarkable variability. Even with complete material I have sometimes found it difficult to fix the limits of a species, although I devoted a great deal of time to the study to the genus while assisting the late Baron von Mueller in the elaboration of his Eucalyptographia, for which I worked up the very extensive material that had accumulated since the publica- tion of the third volume of the Flora Australiensis. This mut- ability of form is well illustrated by the fact that a dozen kinds, raised from Australian seeds, have been described as new species in Europe and America by botanists of repute, although it seems improbable that they would receive seeds of a single species that had not already come under Baron von Mueller's notice. While 32538 A SECTION D. sometimes even a minor character appears to be constant, and affords a pretty sure clue to the identification of a species, in other cases characters that in most plants would be considered of the greatest importance will be found unreliable in Eucalypts. Thus it is also with the bark, which, though generally such a good guide, varies in some instances to a remarkable degree. This is well exemplified by Eucalyptus viminalis ; this tree, which grows around the Melbourne herbarium building, shows here, in its sapling state, a smooth, whitish bark, until it attains a diameter of from 4 to 6 inches, then gradually the outer layers remain attached, at first near the base only, becoming rough and brown ; as the plant gets older, these layers creep higher and higher up the stem, until, in aged trees, the whole of the trunk and also the larger branches are covered with a thick, rugged, dark brown bark. Within 10 miles inland from Melbourne, already the tree changes its character in this respect, inasmuch as only the lower part of the stem is covered with this rugged bark, while another 10 miles further towards the ranges, this species presents a smooth, white trunk, except, perhaps, just near the ground. Although the floral characters remain the same, yet, any one seeing only the two extreme forms would certainly consider them two distinct species. Euc. leucoxylon shows similar anomalies. As another instance of the difficulty of arriving at a correct limitation of the species of Eucalyptus, I may mention the fact that Bentham wrote that after he had finished his description of all the species of this genus for the Flora Australiensis, he considered it neces- sary to re-examine the whole of the collections, a thing which, for want of time, he did not do with any other group of plants. There is one feature which will, probably, throw more light upon the limits of species as well as their affinities, with which we are not yet sufficiently acquainted ; this is the character of the seedlings. I venture to express a hope that in the near future one of our botanic gardens will undertake the investigation of this subject, which requires not only great knowledge and care, but also certain means that are only at the command of few people. . In submitting this contribution to Australian botany, I trust that with all its shortcomings it will prove of some service in identifying the species of our most important genus of timber trees. No. No. Calyx four-toothed ... ... ... ... ... 1 Calyx truncate ... 2 (No. 5, E. tetraptera shows an approach to a four-toothed calyx.) 1. Fruit fully J inch long, E. tetrodonta. Fruit under J inch long, E. odontocarpa. (Probably a variety of the above.) DICHOTOMOUS KEY TO THE EUCALYPTUS. 3 No. No 2. Stamens united in four bundles ... ... ... 3 (This character is generally also discernible in the fruit by four depressions where the stamens had been inserted. ) Stamens free and inserted all around the inside of the calyx ... ... ... ... ... ... 5 3. Fruit more than 1 inch in diameter, convex above the rim of the calyx, E. erythrocorys. Fruit less than 1 inch in diameter, the valves enclosed 4 4. Leaves mostly opposite, ovate-lanceolate, mealy-white, E. tetragona. Leaves scattered, lanceolate-falcate, dull green, E. eudesmioides. 5. Fruit quadrangular, about 1J inches long, reddish, E. tetraptera. Fruit terete or irregularly angular ... ... ... 6 6. Fruit- valves quite enclosed in the capsule ... ... 7 Fruit- valves either quite exserted or the points reaching the level of the rim 64 7. Flowers mostly paniculated ... ... ... ... 8 Flowers in simple umbels ... ... ... ... 35 (Occasionally the inflorescence will appear paniculated in this section through the falling off of the leaves. ) 8. Leaves mostly opposite... ... ... ... .. Leaves scattered ... ... ... ... .. 9. Leaves connate 10 Leaves not connate ... ... ... ... ... 11 10. Leaves about 6 inches long, 3 inches broad, E. perfoliata (allied to No. 31, E. corymbosa). Leaves not exceeding 2 inches in length, E gamophylla. 1 1 Leaves mostly ovate, not exceeding 2 inches in length Leaves lanceolate, at least 3 inches long 12. Calyx bristly, E. setosa. Calyx glabrous, E. aspera. 13. Fruit ^ to ^ inch in diameter, E. ferruginea. Fruit not exceeding J inch in diameter, E. clavigera. (E. (jrandifolia and E. Papuana are varieties of this.) 14. Leaves mostly peltate, E. peltata. Leaves attached to the stalks at the base ... ... 15 15. Leaves of equal colour on both sides ... ... ... 16 (See also Nos. 31 and 34.) Leaves paler beneath than above ... ... ... 24 16. Fruit at least \ inch in diameter, more or less urceolate 17 Fruit rarely exceeding -J inch ... ... ... ... 19 4 SECTION D. No. No, 17. Flowers and fruits sessile, E. eximia. Flowers and fruits pedicellate ... ... ... ... 18 1 8. Leaves lanceolate, operculum double, E. maculata (this in- cludes as varieties E. citriodora and E. melissiodora). Leaves ovate, operculum single, E. latifolia. 1 9. Leaves from orbicular to ovate, E. polyanthema. (E. populifolia, which sometimes has the valves barely exserted, is readily distinguished by the dark, shining leaves, those of E. polyanthema being quite dull and greyish-green.) Leaves from lanceolate-falcate to ovate-lanceolate ... 20 20. Operculum conical, E. kemiphloia. (This includes E. albens as a mealy- white variety, and pro- bably, also, E. Bowmani, described from insufficient material. ) Operculum hemispherical, rarely shortly conical ... 21 21. Leaves ovate-lanceolate... ... ... ... ... 22 Leaves lanceolate ... ... ... ... ... 23 22. Fruit truncate-ovate, about 2 lines long, E. Behriana. Fruit urceolate, 1 line long, E. brachyandra. 23. Leaf-veins very oblique, not numerous, anastomosing, E. largiflorens ( = E. bicolor, Cunn.). Leaf-veins very diverging, numerous, hardly anasto- mosing, E. tesselaris. 24. Fruit with 'eight prominent longitudinal ridges, over 1 inch long, E. ptycliocarpa. Fruit without prominent ridges ... ... ... 25 25. Branchlets with ferrugineous hairs, E. Torelliana. Branchlets glabrous ... ... ... ... ... 26 26. Fruit urceolate ... .'. 27 Fruit ovate or globose-truncate .., ... ... 33 27. Fruit not exceeding 4 lines in length, E. trachypldoia. Fruit over J inch long ... ... ... ... ... 28 28. Operculum broader than the calyx, E. Watsoniana. Operculum not broader than the calyx ... ... 29 29. Fruit under 1 inch in diameter ... ... ... 30 Fruit exceeding 1 inch in diameter ... ... ... 32 30. Peduncles stout, pedicels none, E. Abergiana. Peduncles slender, flowers pedicellate ... ... ... 31 31. Leaves lanceolate, E. corymbosa. (Including as varieties E. terminalis, E. dichroraophloia, and E. pyrophora, as I find it impossible to draw a clear line of demarcation ; the specimens from the dry interior and from the north-west have the leaves frequently of equal colour on both sides, and the fruits are occasionally rather ovate-truncate than urceolate.) Leaves very large, ovate, E. Foelscheana* DICHOTOMOUS KEY TO THE EUCALYPTUS. 5 No. No. 32. Flowers white, rarely pink ; seeds very large, black, not winged, E. calophylla. Flowers red ; seeds brown, winged, E. ficifolia. 33. Fruit truncate^globular, sessile, E. Howittiana. Fruit truncate-ovate, pedicellate 34 34. Operculum depressed-hemispherical, E. Cloeziana. Operculum more or less conical, E. paniculata. (The variety fasciculosa from the dry north-west of Victoria differs in having the leaves of equal colour on both sides and the bark of the trunk smooth.) 35. Fruit two-celled, E. phoenicea. Fruit with three or more cells 36 36. Fruit nearly 2 inches long, E. miniata. Fruit not exceeding 1 inch ... ... ... ... 37 37. Operculum projecting beyond the rim of the calyx ... 38 Operculum not broader than the calyx 39 38. Leaves somewhat paler beneath, E. corynocalyx. Leaves of equal colour on both sides, E. urnigera. 39. Leaves opposite... ... ... ... ... ... 40 Leaves scattered ... ... ... ... ... 41 40. Leaves orbicular, E. Kruseana. Leaves lanceolate, E. doratoxylon. 41. Leaves with several longitudinal veins almost parallel with the midrib ... ... ... ... ... 42 Leaves with the veins all more or less diverging from the midrib ... ... ... ... ... ... 43 42. Operculum conical, leaves rather small, E. stellulata. Operculum hemispherical, leaves large, E. coriacea (= E. pauciflora). 43. Leaves much paler beneath, E. diver sicolor. (Occasionally cultivated under the name of E. colossea. E. marginata has the valves sometimes enclosed, and is then distinguished from E. diversicolor by the conical operculum. ) Leaves of equal colour on both sides or nearly so ... 44 44. Pedicels elongated ... ... ... ... ... 45 Pedicels short or none ,.. ... ... ... ... 47 45. Operculum hemispherical, E. sepulcralis. Operculum conical ... ... ... ... ... 46 46. Leaf-veins very spreading, E. longifolia. Leaf-veins very oblique E. leucoxylon 47. Fertile seeds membranously winged, E. Todtiana. Fertile seeds not winged ... ... ... ... 48 6 SECTION D. No. No. 48. Fruit much contracted at the orifice, nearly globular Fruits but slightly or not at all contracted ... ... 50 49. Fruits nearly 1 inch in diameter, E. buprestium. Fruits about J inch in diameter, E. piperita. (Some specimens from near Port Jackson have almost urceo- late fruitSj but seem gradually to pass into the other form. ) 50. Fruits nearly 1 inch in diameter, E. Planchoniana. Fruits rarely exceeding \ inch ... ... ... ... 51 51. Peduncles mostly recurved ... ... ... ... 52 Peduncles erect... ... ... ... ... ... 53 52. Operculum conical, E. decurva. Operculum hemispherical, E. Cooperiana. 53. Base of the calyx as well as of the operculum abruptly dilated into a furrowed ring, E. torquata. Base of calyx and operculum without these dilatations 54 54. Peduncles short and thick, usually much flattened, E. incrassata. (An extremely variable species ; E. dumosa seems to pass into it by almost imperceptible degrees, although it can generally be distinguished by smaller flowers and fruits and less flattened peduncles. E. grossa, which is the same as E. pachypoda, appears to be also a variety with blunt, but rather long, operculum. See also No. 108, E. goniantha. ) Peduncles nearly terete, mostly slender ... ... 55 55. Calyx angular ... ... ... ... ... ... 56 Calyx terete 57 56. Fruit about J inch long, E. gracilis. Fruit about J inch long, E. ochropkloia. (Perhaps a variety of the above). 57. Calyx and operculum granular rough ... ... 58 Calyx and operculum smooth ... ... ... ... 60 58. Large tree, with fibrous bark ; leaves mostly very inequilateral, E. obliqua. (Sometimes cultivated under the name of E. fissilis.) Shrubs or small trees with smooth bark ... ... 59 59. Leaves rather small, nearly straight, E stricta. (This is the typical E. stricta of Sieber, well described in Mueller's Eucalyptographia, with reniform anthers. Bentham, in Flora Austr. Ill, 217, apparently had a mixture of two species before him, describing the fruit of E. stricta, but the anthers of another species. DICHOTOMOUS KEY TO THE EUCALYPTUS. 7 No No. Leaves large, falcate ; umbels generally enclosed in large bracts while in bud, E. virgata. (Although I believe that Baron von Mueller was correct in including this also as a variety in E. stricta, yet I have kept it distinct as the appearance of the extreme forms is so very different. Both seem confined to the south- eastern parts of New South Wales. Bentham had also in this case a mixture before him, viz., a few specimens of the genuine E. virgata, but mostly those of a large tree allied to E. haemastoma, afterwards described by F. v. Mueller as E. Sieberiana. E. obtusiflora seems to have been described by De Candolle from imperfect material ; an original leaf and a sketch of the specimen point, per- haps, to E. haemastoma, but a second leaf is quite different. The name had better be discarded.) 60. Leaves nearly straight, very shining, E. fcecunda. (Includes E. loxophleba as a variety.) Leaves falcate, inequilateral, dull green or hardly shining ... ... ... ... ... ... 61 61. Fruits about J inch in diameter, E. patens. Fruits not exceeding J inch ... ... ... ... 62 62. Fruit generally 5 or 6 celled, E. Bosistoana. Fruit mostly 4-celled ... ... 63 63. Fruit truncate-ovate, E. odorata. Fruit truncate-globular, E. melliodora. (When in flower E. melliodora is readily distinguished by the outer stamens being sterile. In Mueller's Eucalypto- graphia the anthers are not correctly drawn ; they open by terminal pores.) 64. Flowers generally paniculated ... ... ... ... 65 Flowers mostly in simple umbels ... ... ... 74 65. Leaves distinctly paler beneath, E. Raveretiana. Leaves of equal colour on both sides ... ... ..; 66 66. Leaves opposite... ... ... ... ... ... 67 Leaves scattered . . ... ... ... ... 68 67. Fruit truncate-ovate, about 4 lines long (a box-tree) E. pruinosa. Fruit truncate-globular, 2 or 3 lines long (an ironbark tree), E. melanophloia. 68. Leaves ovate, or orbicular ... ... ... ... 69* Leaves lanceolate ... ... ... ... .., 70 69. Calyx about 3 lines in diameter, E. oligantha. Calyx under 2 lines in diameter, E. populifolia. 70. Operculum about 3 lines long, E. siderophloia. Operculum not exceeding 2 lines 71 8 SECTION D. No. No 71. Fruit-valves much exserted, E. microtheca. (As pointed out already by Baron von Mueller, in hisEucalyp- tographia, Turczaninow's E. brachypoda, to which Mr. Bentham referred this, must be some other species, prob- ably an aberrant form of a known plant.) Fruit-valves level with, or hardly projecting beyond the rim ... 72 72. Fruit 3 to 4 lines in diameter, E. drepanophylla. (Includes as a variety E. leptophleba. ) Fruit not exceeding 2 lines 73 73. Leaves linear-lanceolate, E. crebra. Leaves ovate-lanceolate, lemon-scented, E. Staigeriana 74. Fruits 2 inches in diameter ... ... ... ... 75 Fruits not exceeding 1 inch ... ... ... ... 76 75. Leaves opposite, E. macrocarpa. Leaves scattered, E. pyriformis. 76. Leaves paler beneath 77 Leaves of equal colour on both sides ... ... ... 86 77. Operculum broader than the calyx, E. robusta. Operculum not exceeding the calyx ... ... ... 78 78. Calyx angular, E. botryoides. Calyx terete 79 79. Fruit J inch or more in diameter ... ... ... 80 Fruit under J inch in diameter ... ... ... 81 80. Fruit-valves very short, hardly exserted, E. marginata. Fruit-valves long, much exserted, E. pellita. (Perhaps a variety of E. resinifera.} 81. Operculum longer than the calyx tube, E. resinifera Operculum shorter than the calyx tube ...' ... 82 82. Leaves much paler beneath, the lateral veins numerous and very spreading ... Leaves slightly paler beneath, the lateral veins not very close and moderately spreading ... ... 84 83. Pedicels very short, or none, E. saligna. Pedicels elongated, E. microcorys. 84. Fruit broadest at the orifice ; fertile seeds much larger than the sterile ones ... ... ... ... 84A Fruit contracted at the orifice ; fertile seeds not much larger than the sterile ones 85 8 4 A. Operculum hemispherical ; fruits small, E. propinqua. Operculum bluntly conical, E, punctata. DICHOTOMOUS KEY TO THE EUCALYPTUS. No. No. 85. Fruit about four lines in diameter, rim thick, E. pilu- laris. Fruit not exceeding three lines, rim thin, E. acme- noides ( = E. triantha in Mueller's Census). 86. Leaves mostly opposite. (SeealsoNo. I38,E.dealbata.) 87 Leaves scattered ... ... ... ... ... 91 87. Fruit about 1 inch in diameter, top-shaped, E. Preis- siana. Fruit rarely exceeding |-inch, truncate-ovate ... 88 88. Leaves connate, E. Perriniana. Leaves not connate (except sometimes in E. JRisdoni) 89 89. Leaves with crenulated margin, E. cordata. Leaves with entire margin ... ... ... ... 90 90. Leaves obtuse, ovate or almost orbicular, E. pulver- ulenta. (This includes E. cinerea as a variety. ) Leaves acute, ovate, E. Risdoni. (Sometimes the leaves are connate, while in age they occa- sionally become alternate, and assume a lanceolate form, verging towards E. amygdalina, with which the plant was combined by F. v. Mueller as a variety. ) 91. Flowers and fruits on long, slender pedicels, fruits rather large ... ... ... ... ... 92 Flowers and fruits on short pedicels or sessile (except sometimes E. Maideni) ... ... ... ... 93 92. Fruit top-shaped, filaments red, E. erythronema (= E. conoidea). Fruit truncate-ovate, filaments whitish, E. caesia. 93. Operculum much broader than the calyx, E. gom- phocephala. Operculum not or slightly broader than the calyx ... 94 94. Calyx and operculum warty ... ... ... ... 95 Calyx and operculum smooth or rough, but not warty 96 95. Leaves lanceolate, E. globulus. Leaves ovate, E. alpina. 96. Leaves not over 1 inch long, E. vernicosa. Leaves much exceeding 1 inch ... ... ... 97 97. Stamens straight in the bud. (See also No. 140, E. tereticornis) ... ... ... ... ... 98 Stamens bent inward in the bud ... ... ... 101 98. Fruits of the umbel connate into one mass, E. Lehmanni (included in E. cornuta by F. v. Mueller). Fruits free 99 99. Fruit-valves ending in long, fine points, E. cornuta. (including as a variety E. annulata. ) Fruit-valves short 100 10 SECTION D. No. No. 100. Leaves lanceolate, E. occidentalis. (including E. macrandra and E. spathulata as varieties. ) Leaves ovate, E. platypus. (Baron von Mueller adopted in his Eucalyptographia Turcza- ninow's name of E. obcordata, which appellation seems to me quite misleading and has no claim to priority.) 101. Fruit from J to 1 inch in diameter 102 Fruit mostly under J inch ... ... ... ... 105 102. Top of fruit nearly flat 103 Top of fruit convex ... ... ... ... ... 104 103. Leaves shining, E. megacarpa. Leaves dull, very coriaceous, E. cosmopliylla. 104. Calyx terete, E. Oldfieldi. (E. Drummondi seems a variety of this, being smaller in all its parts.) Calyx angular, E. pachyphylla. 105. Leaves ovate, but acute, rarely ^ovate-lanceolate, E. alba. (E. platyphylla I cannot distinguish from this, even as a variety. ) Leaves lanceolate, rarely linear 106 106. Calyx and operculum strongly ribbed 107 Calyx and operculum not ribbed ... ... ... 109 107. Operculum quite hemispherical, E. corrugata. Operculum elongated ... ... ... ... ... 108 108. Operculum obtuse, E. goniantha, Operculum pointed, E. falcata. 109. Calyx angular, pedicels flattened, E.goniocalyx. Calyx and pedicels terete ... ... ... ... 110 110. Fruit-valves ending in fine points ... ... ... Ill Fruit- valves short, often deltoid ... ... ... 114 111. Capsule raised above the rim... ... ... ... 112 Capsule inserted below the rim ... ... ... 113 112. Operculum conical, flowers closely sessile E. decipiens Operculum hemispherical, E. pallidifolia. 113. Leaves generally dull greyish-green, E. oleosa. Leaves shining on both sides, E. salmonophloia. 114. Capsule inserted below the rim of the calyx or on a level with it ... ... ... ... ... ... 115 Capsule raised above the rim ... ... ... ... 131 115. Leaves linear, E. angustissima. (See also No. 130 E. amygdalina. ) ] Leaves lanceolate. ... ... ... ... ... 116 116. Fruit urceolate, E. Baileyana. Fruit mostly ovate truncate, never urceolate ... 117 DICHOTOMOUS KEY TO THE EUCALYPTUS. 11 No. No. 117. Pedicels very slender, at least three times as long as the calyx, E. leptopoda. Pedicels short ... ... ... ... ... ... 118 118. Operculum conical or acuminate, longer than the calyx 119 Operculum hemispherical, mostly blunt, usually shorter than the calyx ........... , ... 120 119. Flowers shortly pedicellate, E. redunca. Flowers sessile, E. concolor. 120. Leaf -veins fine, numerous, very divergent ... ... 121 Leaf-veins not numerous, very oblique ... ... 122 121. Stamens of expanded flowers, straight, E. cneorifolia. Stamens of expanded flowers bent inwards about the middle, E. uncinata. (E. micranthera is a variety of this.) 122. Peduncles conspicuously flattened near the top, E. salubris. Peduncles nearly or quite terete ......... 123 123. Leaves under 3 inches long ... ... ... ... 124 Leaves mostly over 3 inches long ... ... ... 125 124. Fruit almost flat on top, E. cocci/era. Capsule somewhat sunk below the narrow rim, E. Gunnii (typical.) 125. Fruit topshaped, leaves somewhat undulate, E. Gunnii, var. (I doubt whether Baron Von Mueller was correct in includ- ing this tree in E. Gunnii as a variety in his Eucalypto- graphia, where the main figure represents it. Bentham's description of E. Stuartiana refers partly to this. Perhaps it will be necessary to distinguish it as a separate species, and the name of E. undulata would not be inappropriate.) Fruit ovate or globose, truncate ... ... ... 126 126. Rim of fruit narrow, the valves inserted somewhat below it .................. 127 Rim of fruit rather broad and flat ... ... ... 128 127. Flowers generally 3 in an umbel, E. Bauerleni. (The real affinity is with E. vimincdis.) Flowers more than 3 in an umbel, E. eugenioides. (The real affinity is with E. piperita.) 128. Leaves very pale, bark of stem hard and rugged, E. Sieberiana. Leaves green, bark of stem smooth or fibrous ... 129 129. Fruit ovate-truncate, top of fruit reddish, E. haemas- toma. Fruite globose, truncate or shortly ovate ... ... 130 130. Leaves rather small, their oildots large and not very numerous ; stem-bark fibrous, E. amygdalina. (E. dives is an aberrant form of this. There is a variety in Tasmania with linear leaves.) 12 SECTION D. No. No Leaves large, their oildots very fine and numerous ; stem-bark fibrous only near the base, E. regnans. (Probably correctly included in E. amygdalina as a variety by Bentham and Mueller.) 131. Leaves small, thick, hardly inequilateral, E. santa- lifolia. (Includes E. pachyloma). Leaves mostly large, inequilateral ... ... ... 132 132. Stems of young plants and offshoots quite quad- rangular, with opposite ovate bluish-white leaves, E. Maideni. (I find the above the most striking character in this remark- able species. The typical specimens have rather numer- ous flowers in an umbel, clavate and smooth in bud, with hemispherical but pointed operculum, and a rather long flattened peduncle. But there are forms, especially specimens collected in Gippsland by Mr. A. W. Howitt, that show an unmistakable approach to E. globulus, which in its ordinary form has such a different appearance. In other respects there is an evident affinity with E. goniocalyx. All three species have in their young state quadrangular stems and bluish leaves ; the adult leaves are also somewhat similar in shape and texture. In my opinion, there are weighty reasons against the assumption that we have here a case of hybridisation, but must rather ascribe it to evolution. ) Stems of young plants nearly terete... ... ... 133 133. Veins of leaves very oblique ... ... ... ... 134 Veins of leaves very diverging ... ... ... 136 134. Flowers and fruits sessile, E. capitellata. Flowers and fruits on short pedicels ... ... ... 135 135. Operculum conical, E. macrorhyncha. Operculum hemispherical, E. Muelleri. 136. Flowers mostly three in an umbel, E. viminalis. Flowers more than three in an umbel ... ... 137 137. Operculum nearly hemispherical or shortly and bluntly conical ... ... ... ... ... 138 Operculum conical or acuminate ... ... ... 139 138. Leaves green, alternate, E. Stuartiana. (Distinguished from E. viminalis when the latter has more than three flowers in an umbel by the fibrous bark and roundish seedling leaves, E. viminalis having either a smooth or a rugged but never fibrous bark and lanceolate seedling leaves.) Leaves ashy-grey, sometimes opposite, E. dealbata. 139. Operculum mostly ending in a beak, E. rostrata. (Some varieties have a blunt operculum and form a con- necting link between this and E. tereticornis. E. exserta is a variety. ) Operculum conical, not beaked ... ... ... 140 DICHOTOMOUS KEY TO THE EUCALYPTUS. 13 No. 140. No. Bark smooth ; fruit almost globose through the broad ascending rim, E. tereticornis. Bark rough ; rim of fruit only slightly ascending, E. rudis. E. orbifolia and E. patellaris, enumerated in the "Flora Aus- traliensis" I have omitted, as they have in my opinion been described from too imperfect material to make their recognition at all certain ; also E. Lansdowniana, F. v. Mueller and J. E. Brown, as I have neither a specimen nor the description, and as Professor Tate, who has seen the plant, informs me that he does not consider it a tenable species. Nor could I take cognisance of supposed new species described in recent years from cultivated plants in Europe and America, as it seems inconceivable that seeds of a number of new species should have been sent away while the trees remained unknown to Australian botanists. INDEX. Eucalyptus Abergiana, F. v. Mueller ... acmenoides, Schauer alba, Reinw albens, Miq , alpina, Lindl amygdalina, Labill angustissima, F. v. M annulata, Benth aspera, F. v. M Baileyana, F. v. M Bauerleni, F. v. M Behriana, F. v. M bicolor, Cunn Bosistoana, F. v. M botryoides, Smith Bowmani, F. v. M brachyandra, F. v. M brachypoda, Turcz buprestium, F. v. M caesia, Benth calophylla, R. Br capitellata, Smith cinerea, F. v. M citriodora, Hook clavigera, Cunn Cloeziana, F. v. M cneorifolia, D.C coccifera, Hook, f colossea, F. v. M concolor, Schauer conoidea, Benth Cooperiana, F. v. M cordata, Labill No. 30 85 105 20 95 130 115 99 12 116 127 22 23 62 78 20 22 71 49 92 32 134 90 18 13 34 121 124 43 119 92 52 89 Eucalyptus No. coriacea, Cunn 42 cornuta, Labill 99 corrugata, Luehm 107 corymbosa, Smith 31 corynocalyx, F. v. M 38 cosmophy lla, F. v. M 1 03 crebra, F. v. M 73 dealbata, Cunn 138 decipiens, Endl 112 decurva, F. v. M 52 dichromophloia, F. v. M. ... 31 diversicolor, F. v. M 43 dives, Schauer 130 doratoxylon, F. v. M 40 drepanophylla, F. v. M 72 Drummondi, Benth 104 dumosa Cunn 54 erythrocorys, F. v. M 3 erythronema, Turcz 92 eudesmioides, F. v. M 4 eugenioides, Sieber 127 eximia, Schauer 17 exserta, F. v. M 139 falcata, Turcz 108 f erruginea, Schauer 13 ficifolia, F. v. M ... 32 fssilis, F. v. M 58 fcecunda, Schauer 60 Foelscheana, F. v. M 31 gamophylla, F. v. M 10 globulus, Labill 95 gomphocephala, D. C 93 goniantha, Turcz 108 SECTION D. INDEX continued. Eucalyptus No. goniocalyx, F. v. M 109 gracilis, F. v. M 56 grandifolia, R. Br 13 grossa, F. v. M 54 Ounnii, Hook, f 124 haemastoma, Smith 129 hemiphloia, F. v. M 20 Howittiana, F. v. M 33 Incrassata, Labill 54 Kruseana, F. v. M 40 largiflorens, F. v. M 23 latifoliaF. v. M 18 Lehmanni, Preiss 98 leptophleba, F. v. M 72 leptopoda, Benth 117 lencoxylon, F. v. M 46 longifolia, Link 46 loxophleba, Benth 60 macrandra, F. v. M 100 macrocarpa, Hook 75 macrorhyncha, F. v. M 135 maculata, Hook 18 Maideni, F. v. M 132 marginata, Smith 80 megacarpa, F. v. M 103 melanophloia, F. v. M 67 melissiodora, Lindl 18 melliodora, CUUK 63 micranthera, F. v. M 121 microcorys, F. v. M 83 microtheca, F. v. M 71 miniata, Cunn 36 Muelleri, Howitt 135 obcordata, Turcz 100 obliqua, Lher 58 obtusiflora.D. C 59 occidentalis, Endl 100 ochrophloia, F. v. M 56 odontocarpa, F. v. M. 1 odorata, Behr 63 Oldfieldi, F. v. M 104 oleosa, F. v. M 113 oligantha, Schauer 69 pachyloma, Benth 131 pachyphylla, F. v. M 104 pachypoda, F. v. M 54 pallidif olia, F. v. M. ........ 112 paniculata, Smith 34 Papuana, F. v. M 13 patens, Benth 61 pauciflora, Sieber 42 pellita, F. v. M 80 peltata, Benth 14 perfoliata, R. Br 10 Perriniana, F. v. M 88 Eucalyptus No. phoenicea, F. v. M 35 pilularis, Smith 85 piperita, Smith 49 Planchoniana, F. v. M 50 platyphylla, F. v. M 105 platypus, Hook 100 polyanthema, Schauer 19 populifolia, Hook 69 Preissiana, Schauer 87 propinqua, Deane & Maiden 84a pruinosa, Schauer 67 ptychocarpa, F. v. M 24 pulverulenta, Sims 90 punctata, D. C 84o, pyriformis, Turcz 75 pyrophora, Benth 31 Raveretiana, F. v. M 65 redunca, Schauer _ 119 regnans, F. v. M 130 resinifera, Smith 81 Risdoni, Hook, f 90 robusta, Smith 77 rostrata, Schlecht 139 rudis, Endl 140 saligna, Smith 83 salmonophloia, F. v. M 113 salubris, F. v. M 122 santalifolia, F. v. M 131 sepulcralis, F. v. M 45 setosa, Schauer 12 siderophloia, Benth 70 Sieberiana, F. v. M 128 spathulata, Hook 100 Staigeriana, F. v. M 73 stellulata, Sieber 42 stricta, Sieber 59 Stuartiana, F. v. M 138 tereticornis, Smith 140 term inalis, F. v. M 31 tesselaris, F. v. M 23 tetragona, F. v. M 4 tetraptera, Turcz 5 tetrodonta, F. v. M 1 Todtiana, F. v. M 47 Torelliana, F. v. M 25 torquata, Luehm 53 trachyphloia, F. v. M 27 triantka, Link 85 uncinata, Turcz 121 widulata, Luehm 124 urnigera, Hook, f 38 vernicosa, Hook, f 96 viminalis, Labill 136 virgata, Sieber 59 Watsoniana, F. v. M 28 Sydney : William Applegate Gullick, Government Printer. 1S9S.