(200 ) 
quadrilocular ; fuscescent ; 0,012-0,018™™ long, and 0,004-0,006™™- wide. 
— 0. varia (Pers.) Fr., is common on trunks, throughout the United 
States, and has occurred (f. diaphora) on sandstone in California (Mr. 
Bolander). Spores dactyloid; 4-5-6-locular ; often coloured, but per- 
haps the most perfect ones colourless; in eights, in obovate-clavate thekes. 
— 0. atra (Pers.) Nyl., is perhaps also not uncommon, but I have met 
with it (in the fine var. hapalea, Ach.) only at Chelsea, Mass.; and received 
it only from New Bedford (Mr. Willey). Spores short-dactyloid, quadri- 
locular, in short, often pyriform thekes.—— 0. vulgata, Ach., Nyl., is 
found on trunks throughout the country, and is especially common south- 
ward. It passes also to shaded rocks (f. lithyrga) in Weymouth, Mass. 
(Mr. Willey). Spores fusiform; 3-6-locular ; colourless; in clavate thekes. 
—— 0. Bonplandi, Fée (Ess. p. 25; Suppl. p.19, pr. p. Nyl. Lich. exot. 
1. c. p. 229, & in Herb. Lindig n. 2613) appears to be represented by a 
lichen from the low country of South Carolina (Mr. Ravenel) the blunt- 
fusiform, not rarely fuscescent spores of which, becoming 7-9-locular, 
remind one alittle, at least in their colourless state, of the spores of certain 
forms of Lecanactis premnea. In the reference of our lichen to 0. Bon- 
plandi, I include in my view of the latter, O. abbreviata, Fée, as scarcely 
other than a variety (Nyl. Lich. exot. Lindig Herb. n. 2719). The plant 
before us is closely akin to another tropical lichen, — O. prosodea, Ach. 
(Nyl. Lich. exot., I. c., p. 229) with coarse, thick, prominent fruit, which, 
occurring in Cuba, should not improbably also come within our limits. 
— 0. viridis, Pers. (Nyl. Lich. Scand. p. 256. O. rubella, Moug. & Nestl. 
n. 648) often resembles, and was referred to O. herpetica by Acharius, but 
differs essentially in the internal characters. I have found it in Massa- 
chusetts, on the bark of Conifere ; and Mr. Willey (New Bedford) on 
Beech; and it may also be represented by some southern lichens (North 
Carolina, Rev. Dr. Curtis; South Carolina, Mr. Ravenel; Florida, Dr. 
Chapman) which differ sufficiently in their minuteness at least, from 
O. prosodea. Should this last however occur with us, and, as is possible, 
in small forms, it may well include the southern plants here cited under 
0. viridis. Spores of O. viridis broad-elongated-fusiform; 10-14-locular; 
in short, clavate-oblongthekes. 0. herpetica, Ach., Koerb.,is yet unknown 
here; the lichen so named in Halsey’s catalogue of New York lichens 
(1823) not having been determined by the spores, and being referable, by 
the synonymy, to O. viridis ; as is also the O. herpetica of the present 
writer’s Syn. Lich. N. Eng. p. 75. —— 0. astrea, Tuck. (Lich. Calif. p. 33). 
Upon Holly, Elm, Maple and Bald Cypress, in the low country of South 
Carolina; and in southern Texas (Mr. Ravenel). It occurs also in the 
island of Cuba (Mr. Wright) and is very remarkable for the white vesture 
of its apothecia, which have the aspect rather of Graphis. Spores in 
eights, in clavate thekes; dactyloid; 4-6-8-locular (the cells squared) 
fuscescent, or decolorate ; 0,016-0,025™"- long, and 0,005-0,007™™- wide. 
