EUCALYPTUS PACHYPHYLLA. 



F. v. M., in the Journal of the Linnean Society 1859, pp. 83, 98 and 101 ; Bentham, flora Australiensis iii. 237 (1866) ; 



F. v. M., fragmenta phytographise Australia x. 6 (1876). 



Shrubby ; branchlets robust, not very angular ; leaves scattered, on long stalks, of thick 

 leathery consistence, ovate- or broad-lanceolar, hardly unequal-sided, very finely veined, not 

 conspicuously dotted, the marginal vein distinctly removed from the edge ; stalk very short, bearing 

 several flowers either sessile or on short stalklets ; calyx with 4-7 longitudinal angles ; the lid 

 semiocate and acuminate, twice as long as the tube ; stamens yellow, inflected before expansion, 

 with almost ovate anthers, their cells opening with longitudinal slits ; style elongated ; stigma not 

 dilated ; fruit depressed-hemispherical, usually with 4 prominent angles, with a broad ascending 

 rim and 4 or 5 rarely 3 slightly exserted valves ; placental axis nearly as broad as long ; sterile 

 seeds slender ; fertile seeds surrounded by a narrow membrane. 



In the deserts of Central Australia, known from Sturt's and Hooker's Creek to Lake Amadeus 

 and MacDonnell's Range (F. M. ; E. Giles). 



The peculiar shape of the fruit distinguishes this species already from any other. The plant 

 has merits for decorative culture in shrubberies and will bear the hottest drought. The heat, which 

 this and other Central-Australian plants will endure, may exceptionally rise in the shade to 122 F., 

 and in the sun to 104 F., or even as observed by McKinlay to 168 F. in the suii, and as noted 

 by Sturt to 132 F. in the shade. This extraordinary endurance of heat, shown by some Eucalypts, 

 finds to some extent its explanation in the great power of exhalation possessed by these plants. 



EXPLANATION OF ANALYTIC DETAILS. 1, longitudinal section of an unexpanded flower ; 2, front-view of an 

 anther with the upper part of its filament ; 3, back-view of the same ; 4, pistil ; 5, transverse section of young fruit ; 

 6, longitudinal section of fruit ; 7, sterile seeds ; 8, fertile seeds ; 9, pollen-grains, these diametrically 300 times 

 magnified. The augmentation of the other details readily rated by comparison of the main figure, which is of 

 natural size. 



The Stomata or breathing-pores of the epidermis of leaves occur in about equal number on 

 both pages in E. pachyphylla as in the majority of cases in Eucalypts, numbering in this instance 

 about 40,000 to each square inch. This seems an apt opportunity to adduce the results, which by 

 microscopic observations and micrometric measurements have been obtained concerning the 

 number and distribution of the stomata in different species of this very large genus. As in 

 Proteacea? so in Eucalyptea) the occurrence of the stomata, whether on the underside of the leaves 

 alone,, or on both pages in unequal or in equal numbers, indicates three series, according to which 

 the species have been tabulated below. In the time-absorbing elaboration of these details I have 

 been aided by Mr. L. Hummel. 



TABLE or APPROXIMATE NUMBER OF STOMATA PER SQUARE INCH OF EUCALYPTUS LEAVES. 

 I. Stomala hypogenous = on the underside only. 



Eucalyptus Abergiana ... 180,000-228,000 



acmenoides ... ... 149,000-210,000 



botryoides ... ... 105,000-116,000 



brachyandra ... ... ... 224,000 



calophylla ... ... 207,000-230,000 



Clocziana ' ... ... 310,000-311,000 



corymbosa ... ... 100,000-157,000 



Decaisneana ... ... ... 207,000 



dirersicolor ... ... 170,000-228,000 



Eucalyptus flcifolia ... ... 140,000-161,000 



microcorys ... ... 210,000-211,000 



pellita ... ... 150,000-155,000 



ptychocarpa ... ... ... 240,000 



resinifera ... ... 139,000-160,000 



robusta ... ... 155,000-195,000 



Ravcretiana ... ... 220,000-248,000 



saligna ... ... 155,000-217,000 



trachyphloia 124,000 



