EUCALYPTUS INCEASSATA. 



upper portion of the lid broader and more blunt, while the anthers seem invariably heartshaped- 

 globular, so far as this plant, of which we have as yet no ripe fruit, is known. 



E. micranthera, which is closely connected with the arboreous and soft-barked E. decipiens, 

 differs from the genuine E. incrassata particularly in its very short and almost heartshaped 

 anthers, but in other respects comes near to the variety so long separated as E. dumosa. 



E. grossa (from which E. pachypoda, F. v. M., fragmenta phytographiaj Australia vii. 41 

 anno 1869, is only separable as a variety) can best be distinguished from E. incrassata by its not 

 distinctly compressed though stout umbel-stalks, by the slightly angular but not furrowed tube of 

 the calyx, by the semiellipsoid even lid, by the filaments inflexed near or towards the summit 

 only, and by its not angular fruit with no narrow apex of the valves. 



The specific name, adopted by the French naturalist, seems to refer to the leathery thickness 

 of the leaves, which however is observable in many other species. E. dumosa represents the 

 small-flowered state with generally narrower leaves, only faintly furrowed and ridged calyces, 

 short-pointed lid and scarcely dilated umbel-stalks. 



Poiteau's drawing of E. incrassata for Labillardifere's work can only with difficulty be 

 reconciled to the species here under consideration, as the lateral veins of the leaves are shown too 

 spreading and too prominent and the calyces quite devoid of furrows and streaks, to which 

 Labillardifere neither alludes in his description, although some specimens, which I gathered at 

 King G-eorge's Sound, but which are aberrant from the common form of E. incrassata, accord 

 sufficiently with the figure authoritative for this species. To this smooth-fruited variety approaches 

 very closely E. cosmophylla, from the Stringybarktree-forests of the mountains on St. Vincent 

 Gulf, which species shows however more pointed generally broader and less shining leaves with 

 more visible veins, the flowers less in number and on a shorter common stalk and rather an 

 increase in the number of fruit-valves. 



E. Planchoniana approaches in some of its characteristics E. incrassata, but irrespective of 

 its not belonging to the desert-country, it is a comparatively tall tree, the leaves are longer, not so 

 shining, have more spreading, more distant and more prominent veins and their stomata only on 

 the lower page, the tube of the calyx is less turgid, the lid more gradually attenuated upwards, 

 the anthers are never elongated to an oblong form, the outer stamens are not bent downward 

 while in bud, but are somewhat flexuous, the valves of the fruit are not narrowly attenuated at 

 their apex, and the fertile seeds are more angular. 



E. incrassata is one of the prevailing species among those, which widely constitute the dense 

 " Mallee-scrub," and plays thus an important part in the natural economy of the desert, aiding to 

 mitigate the excessive heat and the efiect of Sirocco-like blasts of widely arid regions by its 

 enormous power of evaporation, in which respect Eucalypts generally far surpass most other 

 kinds of trees, the power of their roots for drawing up and absorbing humidity from the soil being 

 also very great. It is well known that E. incrassata, E. microtheca and E. oleosa will yield water 

 to a parched traveller from their roots. 



Explanation op Analytic Details. — 1, unexpanded flower, the lid lifted ; 2, longitudinal section of unex- 

 panded flower ; 3, some stamens in situ ; 4, and 5, front- and back-view of an anther, with portion of its filament ; 

 6, style and stigma ; 7, longitudinal section of a fruit ; 8 and 9, transverse section of fruits ; 10 and 11, fertile and 

 sterile seeds ; 12, portion of a leaf ; all magnified, but to various extent. 



