ILLUSTRATIONS (23). ACT C TIL AR- LEAVED VARIETIES. 325 



genus is not dependent on soil and climate but on a 

 specific organization, on internal natural disposition, common 

 alike to the vegetable and to the animal world. With the 

 Araucaria imbricata of Chili, the Pinus Douglasii of the 

 Columbia River, and the Sequoia gigantea of New California 

 ('245 — 300 feet) contrasts most strongly — not the Willow 

 (Salix arctica) stunted by cold or mountain height, and 

 only two inches high, — but a little phanerogamic plant in 

 the beautiful climate of the southern tropical region, in the 

 Brazilian province of Goyaz. The moss-like Tristicha hyp- 

 noicles, of the Monocotyledonous family of the Podostemea?, 

 hardly attains the height of three lines. " While crossing 

 the Rio Clairo in the province of Goyaz," says an excellent 

 observer, " I perceived on a stone a plant, the stalk of which 

 was not more than three lines high, and which I considered 

 at first to be a moss. It was, however, a phanerogamic 

 plant, supplied with sexual organs like our oaks, and those 

 gigantic trees which raised their majestic heads around."* 



Besides the height of the stem, the length, breadth, and 

 position also of the leaves and fruit, the aspiring or horizontal, 

 almost umbellate ramification, the gradation of the colour 

 from fresh or silver- greyish green to dark brown, give a 

 peculiar physiognomical character to the Conifera?. The 

 acicular leaves of Pinus Lambertiana (Douglas) in North- 

 Western America are five, those of the P. excelsa (Wallich) 

 on the southern slope of the Himalaya near Katmandu, seven, 

 and those of P. longifolia (Roxb.) on the mountain range of 

 Cashmere, more than twelve inches long. Moreover, in one 

 and the very same species, these acicular leaves vary in the 

 most remarkable manner, from the combined influence of the 

 nourishment derived from soil and air, and of the height above 

 the level of the sea. I found these variations in the length 

 of the leaves of our common wild pine (Pinus sylvestris) so 

 great, while travelling in a west and east direction over an 

 extent of 80° of longitude (more than 3040 miles) from the 

 Scheldt, through Europe and Northern Asia, to Bogoslowsk, 

 in the Northern Ural, and Barnaul beyond the Obi, that occa- 

 sionally, deceived by the shortness and rigidity of the leaves, 

 I have mistaken it for another species of pine, allied to the 

 mountain fir, P. rohmdafa, Link, (Pinus uncinata, Ram.) 

 * Auguste de St. Hilaire, Morphologie vegetale, 1840, p. 98. 



