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Show 344 PHYSIOGNOMY OF PLANTS. tion, of the birch and common fir in a part of the Swiss Alps, on the Grimsel. The fir (Pinus sylvestris) extends to 5940, and the birch (Betula alba) to 6480 French (6330 and 6906 English) feet; above the birches there is a higher line of Pinus cembra, whose upper limit is 6890 (7343 English) feet. Here, therefore, we have the birch intervening between two zones of Coniferre. According to the excellent observations of Leopold von Buch, and the recent ones of Martins, who also visited Spitzbergen, the following geographical limits were found in Lapland: Pinus sylvestris extends to 70°; Betula alba to 70° 40'; and Betula nana quite up to 71°; Pinus cembra is altogether wanting in Lapland. (Compare Unger tiber den Einfluss des Bod ens auf die V ertheilung der Gewachse, s. 200; Lindblom, Adnot. in geographicam plantarum intra Sueciam distributionem, p. 89; Martins, in the Annales des Sciences naturelles, t. xviii. 1842, p. 195.) If the length and arrangement of the needle-shaped leaves go far to determine the physiognomic character of Coniferre, this character is still more influenced by the specific differences in the breadth of the needles, and the degree of development of the parenchyma of the appendicular organs. Several species of Ephedra may be called almost leafless; but in Taxus, Araucaria, Dammara (Agathis), and the Salisburia adiantifolia of Smith (Gingko biloba, Linn.), the surfaces of the leaves become gradually broader. I have here placed the genera in morphological succession. The specific names first chosen by botanists testify in favor of such a succession. The Dammara orientalis of Borneo and Java, often above ten feet in diameter, was first called loranthifolia; and Dammara australis (Lamb.) of New Zealand, which is 140 (149 English) feet high, was first called zamrefolia. In both these species of trees the leaves are not needles, but "folia alterna oblongo-lanceolata, opposita, in arbore adultiore srepe alterna, enervia, striata." The under surface of the leaves is thickly set with porous openings. This passage or transition of the appendicular system from the greatest contraction to a broad-leaved surface, like all progression from simple to compound, has at once a morphological and a physiognomic interest (Link, Urwelt, th. i. 1834, s. 201-211). The short-stalked, broad, cleft leaf of the Salisburia (Kampfer's Ginko) has also its breathing pores only on |