LEPTOGIUM] COLLEMACE 73 
diellewm Ny]. in Flora xlviii. p. 210 (1865); Cromb. in Journ. 
Bot. xx. p. 272 (1882) & Monogr. i. p. 68. 
The form of the lobes is that of a minute L. fragile or L. Schraderi ; 
they vary from being rather narrow to slender and wiry. 
Hab. On caleareous rocks in hilly districts.—Distr. Rare in W. 
England.—B. M. Cleve Hill, Somerset; Warton Crag, Lancashire. 
17. L. microscopicum Nyl. in Act. Soc. Linn. Bord. sér. 3, 
i. p. 272 (1856).—Thallus effuse, minute, of crowded erect 
slender nodulose branchlets, unequally rounded, somewhat con- 
stricted or attenuate at the base, dark olive-brown. _ Apothecia 
rare, minute, scattered, concave, pale- or reddish-brown, with an 
entire margin ; spores ovoid or oblong, 3—5-septate and muriform, 
22-27 » long, 9-14 » thick.—Leight. Lich. Fl. ed. 2, p. 468; 
ed. 3, p. 34; Cromb. in Journ. Bot. xii. p. 336 (1874). 
Hzsicc. Cromb. n. 7. 
Considered at one time to be a form of L. lacerwm; it is, however, 
distinct in the form of the thallus and in the apothecia, which were 
discovered by Crombie on a specimen collected at Shiere. 
Hab. On the trunks of old trees and on slaty rocks, but chiefly on 
chalk pebbles and calcareous walls in maritime and inland districts.— 
Distr. Local, though common where it occurs in the Channel Islands, 
S. and W. England and 8.W. Highlands, Scotland.—B. M. Rozel 
and coasts of Jersey; near Lewes, Sussex ; near Gomshall and Shiere, 
Surrey; near Maidstone, Kent; Cheddar Cliffs, near Porlock, near 
Clevedon, Yatton, and Weston-super-Mare, Somerset; near Chalford, 
Stroud, Brinscomb aud near Cirencester, Gloucestershire; St. Fagan, 
Glamorganshire; Malvern and Aston, Worcestershire ; Blaxton, York- 
shire; Eden, Westmoreland. 
Thallus of larger lobes, usually dark-brown. 
18. L. Schraderi Nyl. Syn. Lich. i. p. 133 (1858).—Thallus in 
crowded tufts of rather narrow elongate dichotomously branched 
lobes, irregularly wrinkled and somewhat angular, dilated in the 
middle, dull olive-green or dark reddish-brown. Apothecia rare, 
lateral, small, concave, reddish, with an entire paler margin ; 
spores ellipsoid, 3—5-septate and muriform, 23-33 pw long, 11-15 pu 
thick.—Mudd Man. p. 49; Cromb. Lich. Brit. p. 9; Leight. 
Lich. Fl. p. 36; ed. 3, p. 34. Lichen Schraderi Bernh. in 
Schrad. Journ. Bot. i. p. 22, t. 2, fig. 5 (1799). Collema 
Schraderi Ach. Lich. Univ. p. 658 (1810); Engl. Bot. t. 2284; 
Hook. in Sm. Engl. Fl. v. p. 213. Polychidium Schraderi 8. F. 
Gray Nat. Arr. i. p, 402 (1821). Collemodium Schraderi Nyl. ex 
Cromb. in Grevillea xv. p. 12 (1886); Cromb. Monogr. i. p. 62. 
Ezxsicc. Larb. Lich. Hb. n. 4. 
Easily distinguished by the long narrow somewhat erect cylindrical 
lobes which have a distinctly cellular cortex. Sometimes they are 
broader and occasionally very much reduced. 
