442 Lichenes of New England. 
Placodium ochroleucum, De Cand. l. c., Moug. & 
Nestl.! 1. c., Lichen saxicola, Pollich, Ach. Prodr. — 
Tombstones in the (Old) Cambridge burying-ground, 
A pretty species. Specimen v.s. ex Hook. in herb. 
Greene. 
S. élegans, Hook; l. c., Lecanora elegans, Aelii 
Lichenogr. p. 435., Scher. ! 1. c., Hals. 1. c.; Parmelia 
elegans, Ach. Meth. p. 193., Wallr. 1. c., Lichen:ele- - 
gans, Link, Ach. Prodr.— With the last; and on 
pebbles, Cambridge Common. 
PanwELIA Halseyana: thallo substellato pallide 
flavo-virescente nigro-punctato, subtus albo fusces- 
cente fibrilloso, laciniis angustis imbricatis ad cen- 
trum rugosis concretis ; scutellis badiis margine inte- : 
gro. Mountain rocks. — Notch of the White, Moun- 
tains, abundant. Alpine rocks on the Franconia 
Mountains ; and the higher peaks of the Green 
Mountains, Vt. I have ventured to name this in 
honor of the learned author of the * Synoptical View 
of New York Lichens.” The lichen resembles P. 
conspersa, and P, centrifuga, the latter of which I am 
only acquainted with through the descriptions. - It is 
distinguished from the former. by its different habit, 
and the color of the under surface; and from the 
latter by the presence of the little black apophyses | 
on the upper surface, which are also observable on 
P. conspersa. The color is much. brighter than; in 
P. conspersa, and the plant is handsomer. 
~P. aleurites, Ach. Meth. p. 208., Ach. Lichenogr 
p. 484., Moug. & Nestl.! L c., Spreng. 1. c., Wallr. 
lci, Hook.!l c, Hals. l c., Mass. Catal., Lichen 
