(274) 
also, except in their want of colour, to those of P. lewcoplaca, Koerb. 
(Mass. fem. f. 170) with which the author of the species considers it 
best associable. 
2.— SPECIES WITH COLOURED SPORES. 
P. aggregata, Fée Suppl. (Verrucaria, Fée Ess., Ny]. Pyr.). Ontrunks 
(determ. Nyl.) South Carolina (Mr. Ravenel). Alabama (Mr. Beaumont). 
Texas (Mr. Ravenel). Spores varying, as in other species of this section, 
from ellipsoid to cymbiform, or, less commonly, oblong; quadrilocular. 
The habit of the clustered apothecia is altogether that of Trypethelium, 
and TJ. nudum, Fée, belongs here according to Nylander; nor do the spores 
at least of T. nigritulum, Nyl. (Lindig n. 2794) appreciably differ. 
‘Neither of these lichens exhibits any proper stroma. ——P. lewcoplaca 
(Wallr.) Koerb. (P. farrea, Ach. pr. p., Nyl.). Trunks. White Mountains. 
‘Vermont (Mr. Frost). Massachusetts (Mr. Willey). New York (Mr. 
Peck). Spores fuscescent, 4-7-locular, 0,020-0,027™™- long, and 0,005- 
0,007"™™- wide. Paraphyses, as in the other species of this section, distinct. 
—— P. glabrata (Ach.) Mass. (Verrucaria, Ach.). Trunks, New England. 
New Jersey (Mr. Austin). Pennsylvania (Dr. Michener). Spores cocci- 
form, quadrilocular. Ihave not reccived it from the south, but a lichen 
with rather larger, more conical fruit, collected by me in Henrico county, 
Virginia, was referred here by Dr. Nylander. ——P. mamillana (Ach.) 
(Verrucaria, Ach., Nyl.) v. Santensis, Nyl. (V. Santensis, Tuck. tn litt. 
Nyl. Syn. . Caled. p. 88). On various barks. South Carolina (Mr. 
Ravenel). Alabama (Mr. Beaumont). Texas (Mr. Ravenel). The glau- 
eescent apothecia become at length quite naked, as in the ordinary 
tropical state; and the lichen, though scarcely reaching the same size as 
the other, and passing here into even minute conditions, differs chiefly in 
its smaller, more cocciform rather than oblong (quadriloculay) spores. 
These spores, and the remark is equally applicable to the next species, 
oecur also with sharpened tips, or broad-cymbiform, when they are often 
colourless; and such states compare with the cocciform and coloured ones, 
much as the spores of Thelotrema Bahianum, &c., with those of T. cara- 
tum, &c.——P. nitida, Ach. (Verrucaria, Ach., & <Aucett.). Trunks 
throughout the United States. Common from New England southward 
to Virginia. Westward (Lea; Hall). Carolina (Curtis; Ravenel) to 
Louisiana (Hale). Spores more commonly cocciform than those of the 
European lichen (differing therefore much as P. mamillana, ?, from @) 
but occurring also in the ellipsoid and oblong-cllipsoid modifications 
which characterize the type of the latter; quadrilocular. —Var. nitidella, 
Floerk.! Southern States. South Carolina (Mr. Ravenel). Alabama (Mr. 
Beaumont). Texas (Mr. Wright). The apothecia smaller than in a, and 
at length quite immersed (f. punctella, Nyl. Pyr.). P. pachycheila, 
1 Pyrenula pachycheila (sp. nova) thallo hypophlwode ; apotheciis obtectis 
{Omm-, 7-Im™ lat.) 1. solitariis mastoidco-prominulis lL. pluribus in verrucas dif- 
