193 
has been well known for a long time, having been figured by Dillenius 
and characterised by Linneus. According to Scherer, “it hangs, 
frequently in great profusion, from the branches of pine-trees in moun- 
tainous and alpine woods throughout all Europe.” So that it might 
be expected, with considerable probability, to occur in this country. 
It belongs to the section of the genus distinguished by a more or less 
compressed foliaceous thallus, of which the clearly established British 
representatives are E. prunastri, E. furfuracea, E. intricata, and E. 
flavicans. Of these it is most nearly allied to the first-mentioned ; 
but may, however, be very readily known by the pendulous, filiform 
segments of its thallus, and by its differently shaped and coloured 
apotbecia and intricate habit of growth. By age the outer membrane 
of the thallus is ruptured at intervals, and the medullary cord exposed, 
exactly as in the analogous articulate state of Usnea barbata (vide 
Eng. Bot. t. 258, fig. 1). 
3. Cetraria cucullata (L.cucullatus, Bell.) —“ Thallus cartilaginous, 
subfoliaceous, sinuato-lacinate, pale yellowish; margins connivent, 
undulated. Apothecia adnate to the back of the lobes; disk pale 
reddish.”—Fries, Lich. Eur. p. 37. 
Lichen cucullatus, Bell. Osserv. Bot. 154; Smith, Trans. Linn. 
Soc. i. t. 4, fig. 7; Ach. Prod. p.171. Cetraria, Ach. Meth. p. 293 ; 
Lich. Univ. p. 511; Fries, Lich. Eur. p. 37; Summa, 1. p. 103; 
Scher. Spic. ix. 248; Enum. p. 14. Platisma, Hoffm. pl. Lich. 
Lobaria, Hoffm. Germ. Physcia, DeC. 
Exsic. Fries, Lich. Suec. 173; Scher. Helv. 18; Moug. and Nest. 
044. 
Examples of this species are placed amongst a series of specimens 
of C. nivalis, from the “ Cairngorm mountains, Scotch Highlands,” in 
the Daltonian herbarium. 
This lichen belongs to the class of species which, like several 
flowering plants, have their head-quarters in Arctic Europe, and are 
also generally distributed throughout the Continent in alpine and ele- 
vated situations, but do not in the South descend into the low grounds. 
With reference to the Continent, Scherer marks C. nivalis as its “very 
faithful associate ;” but in Britain the relative frequency of the two 
species appears to be reversed, and itis C. cucullata that is the casual 
companion of C. nivalis. Besides resembling each other in their geo- 
graphical distribution, they are also closely allied in habit and appear- 
ance. Sir J. E. Smith says, respecting C. cucullata, that it is 
“apparently intermediate between nivalis and islandica;” but it is 
VOE.” ¥: 2c 
