EUCALYPTUS TETRODONTA. 



F. V. M., in the Journal of the Linnean Society iii. 97 (1858) ; Bentham, flora Australiensis iii. 260. 



Arboreous ; branclilets angular ; leaves opposite, lanceolar-sickleshaijed, opaque, their lateral 

 veins moderately spreading, the intramarginal vein close to the edge ; umbels axillary and solitary 

 or sometimes 2 or 3 jointly terminal, each with 3 or seldom 4-5 flowers ; flowerstalks hardly 

 shorter than the calyx ; stalklets extremely short but angular ; bracts 2, opposite, rather large, 

 slowly deciduous ; tube of the calyx conical-hell&haped, provided slighthj below the margin with four 

 deltoid teeth ; lid hemispherical, smooth ; stamens inflexed before expansion ; anthers oval-oblong, 

 opening with longitudinal slits ; stigma hardly broader than the style ; fruit angular, mostly 

 3-celled, the discal expansion forming a narrow rim beyond the calyx-teeth ; placental axis in age 

 twice as long as broad ; valves enclosed ; sterile seeds not much narrower than the fertile seeds, 

 all without any membranous appendage. 



On the bushy sandstone-tableland of Arnhem's Land (F. v. M.) ; near Port Essington 

 (Leichhardt) ; Port Darwin (Schultz) ; Maria-Island and Liverpool-River (Gulliver) ; Escape- 

 Cliffs (HuUs). 



A kind of Stringybark-tree, but not tall. Stem rather slender. Bark pale, fibrous, coating 

 the branches as well as the stem persistently. Leaves 3-8 inches long, ^1 J inches broad ; the 

 uppermost sometimes alternate. Bracts at the summit of the flowerstalk boatshaped-lanceolar, 

 about \ inch long. Calyx measuring when in flower about \ an inch, when in fruit up to | of an 

 inch in length, so far as hitherto observed. Sterile seeds often narrow-pyramidal and truncated ; 

 fertile seeds mostly oblique-oval. 



This species is highly remarkable aud instructive, inasmuch as the strongly toothed calyx 

 demonstrates some transit towards Angophora, although the lid is noways dissolved into petals 

 as in that genus, nor can the operculum be rightly regarded as petaloid, it being quite of the 

 texture and structure normal in most Eucalypts, indeed in this respect not different from the lid 

 of E. Preissii, E. terminalis, E. Abergiana and a few other species, in which the calyx is rather 

 irregularly ruptured than circumcised by a clearly defined sutural line ; at best only the inner 

 layer of the lid could be assumed to be corollaceous, but it is closely connate with the outer 

 stratum as usual in the genus. 



E. tetrodonta has no immediate close affinity to any of its congeners, except to E. odontocarpa 

 (F. V. M., in the Journal of the Proceedings of the Linnean Society, iii. 98) from the North- 

 Western regions of Central Australia ; this however I found only of shrubby growth, its leaves 

 much narrower, the calyces very considerably smaller on shorter and thinner stalklets, the fruit 

 also of much less size, its minute teeth protruding beyond the outward not decurrent rim. 



Explanation of the Analytic Details. — 1, longitudinal section of unexpanded flower ; 2 and 3, front- and 

 back-view of a stamen ; 4, style ; 5, longitudinal section of a fruit ; 6, sterile seeds ; 7, fertile seeds ; variously 

 magnified. 



I may perliaps avail myself at this early opportunity, while issuing the first plates of the 

 Atlas, to point out, that in any arrangement of the species of Eucalyptus according to the cortical 

 system E. tetrodonta would probably merge into the division of Pachyphloiee, which comprises all 

 the Stringybark-trees. When in 1858 a descriptive essay on those Eucalypts, which from 1855 to 

 1856 I hud personally observed in tropical and eastern subtropical Australia, was offered by me to 

 the Linnean Society, and published in its journal of proceedings iii. 81-101, I explained how by a 

 few simple easily observable characteristics of the bark all Eucalypts could be classified according 



