Lichenes.] THE HIMALAYAN MOUNTAINS. : | 437 
considers them more nearly allied to Fungi than to Alge. They are aérial perennial 
plants, cellular in structure, indefinite in extension, and with no. fixed symmetry of 
form. They are found growing on stones, or on the earth, or on living or dead, but not 
usually on decaying parts of plants, sometimes on the trunks of trees, and sometimes 
on the leaves, especially of tropical evergreens. Pulverulent Lichenes are the first 
plants that clothe the bare rocks of newly-formed islands, then follow foliaceous 
Lichenes, and then Mosses and Hepatice (D’Urville ex Lindley). A certain degree of 
moisture, though less than that required for other Cryptogamic Plants, is necessary 
for the growth of Lichenes: we, therefore, find them flourishing in comparatively dry 
climates with moderate temperatures, but attaining perfection in the moist seasons of 
the year; abounding also, but less frequently forming fructification, in much colder 
regions, and thus extending from the equator to polar regions, and from the rocky 
shores of the ocean to the verge of perpetual snow. It has been remarked that the ’ 
same species are found in very different parts of the world, and that the Lichens of 
Europe differ little from those of North America; Mr. Brown long ago enumerated 
the European species in New Holland, and Baron Humboldt, (Syn. Pl. Aquinoet. 
Orbis Novi,) has since mentioned those in the mountains of South America. 
This is observed, but in a still more remarkable manner, in the comparatively few 
Lichens which I collected in the Himalayas, almost the whole of which are pronounced 
by Professor Don, who has had the kindness to examine and compare them, to be 
identical with European species, and J can add my testimony to his, as I am unable 
to perceive any specific difference in those which I have compared. 
Among the most conspicuous of the Himalayan Lichenes, are Usnea barbata and 
U. florida ; the former extending south to Ceylon and the Peninsula of India, especially 
to Coorg; the latter is found on Chimborazo in S. America, and in New Holland. 
Borrera furfuracea and B. ciliaris, equally European species, are both very common, 
especially the former, in the Himalayas. To this genus belongs the Lichen (B. Ashneh, 
nob.), which is called chulchelera, and so extensively employed in India as a dye. 
B. ciliaris is also found in Coorg, and Roccella fuciformis, or flat-leaved Orchil, very 
abundantly in Tranquebar. Ramalina farinacea is extremely abundant in the Hima- 
layas, and found also in the Peninsula, in the Hills near Cudalore. Of Gyrophora, 
a. species which is closely allied to, if it be not identical with G. murina ; while of Pelti- 
dea, P. canina, is found on the Choor mountain ; Parmelia perlata, caperata, physodes, 
and aipolia, with Sticta pulmonacea and scrobiculata, are indigenous in the Himalayas, as 
well as in Europe. Besides these are other species of the former genus, as well in 
the Himalayas a8 in the Peninsula. In the former are also found a species of Alectoria, 
an A. jubata?, with Stereocaulon paschale, and species of Cladonia and Scyphophorus. 
Numerous species of crustaceous Lichens may also be seen, both on trees and rocks, 
‘on the mountains, as well as in the ‘plains. The few in Herbaria belong to the 
genera Lecanora, Lecidea, Lepraria, Pertuasaria, Endocarpon, Verrucaria, Opegrapha, 
and Arthonia. From Bombay specimens have been sent of Usnea barbata and Jlorida, 
with 
