52 
Ohio Biological Survey 
condition on calcareous rocks. Previously recorded for Ohio, but we 
have not seen the specimens. 
3. Collema microphyllum Ach. Lich. Univ. 630. 1910. 
Transforming the algal-host colony into a minute, suborbicular or 
irregular body, which is 0.1 to 1 cm. across, 110 to 160 mic. thick, and 
closely adnate or sometimes raised at the margin, with the marginal 
lobes rounded and those toward the center reduced, granulate-crenate, 
and often imbricate, with the upper surface black-olive, and with the 
algal chains somewhat more numerous toward the upper surface; thallus 
of densely disposed, much branched hyphse, which are uniformly distri¬ 
buted, extend in various directions, and are 2.6 to 4 mic. wide; rhizoids 
hyaline, numerous at certain points, especially under the apothecia; 
apothecia numerous, minute or small, sessile, or adnate, 0.3 to 0.6 mm. in 
diameter; disk concave to flat, red- to dark-brown, surrounded by an 
entire thalloid margin which does not extend above it and often becomes 
overgrown; exciple plectenchymatous, hyaline; hypothecium plectenchy- 
matous below and of interwoven hyphae above, 55 to 80 mic. thick; 
hymenium 90 to 120 mic. thick; asci 85 to 95 mic. long and 21 to 26 
mic. wide; spores longitudinally 4-celled and transversely 2-celled, 18 
to 25 mic. long and 9 to 13 mic. wide. See Figs. 10, 12, and 23. 
Collected near Peebles, by Bruce Fink, No. 64. On tree trunks. 
Not ])reviously recorded for Ohio. 
4. Collema plicatile Ach. Lich. Suec. 129, 237. 1798. 
Lichen plicatilis Ach. Vet. Akad. Flandl. i6: 11. pi. 1. f. 2. 1795. 
Transforming the algal-host colony into a small, irregular or subor¬ 
bicular, somewhat coriaceous body, which is 0.4 to 2.5 cm. across, 185 
to 370 mic. thick, and loosely attached to the substratum, with more or 
less imbricated, ascending or erect lobes with plicate-crisped margins, 
with the upper surface black-olive, with the lower surface scarcely lighter 
colored, and with the algal chains scattered toward the center but numer¬ 
ous toward the surfaces; thallus of densely and variously disposed 
hyphie, which are 3 to 5 mic. wide; rhizoids rare, except at the points of 
attachment of the thallus to the substratum; apothecia small, sessile, scat¬ 
tered, 0.5 to 1 mm. in diameter; disk concave to flat, red- to dark-brown, 
surrounded by an entire thalloid margin, which does not extend above it; 
exciple very thin, of interwoven hyphie, tinged with brown ; hypothecium 
of interwoven hyph?e, light brown, 90 to 105 mic. thick; hymenium 130 
to 160 mic. thick; asci 80 to 95 mic. long and 14 to 18 mic. wide; spores 
