(160 ) 
(Syst. p. 209, where the supposed structural deficiency is relied on as a 
character of the new genus Pyrrhospora) and the European lichen agrees 
infact, in this respect, aselsewhere (Obs. Lich. 1.¢. 6, p. 275) indicated, with 
the American. Spores of our plant reddish-brown in the thekes, and 
more rarely when free ; the colourless ones appearing possibly most per- 
fect.—B. lucida (Ach.) Fr., resembling rather a member of the, 
lecanorine group represented by Lecanora varia, and occurring in fissures 
of rocks, and also on dead wood (Fr.) has been found, in the latter 
habitat, in Arctic America by Richardson (Hook. Append. Frankl. Narr.) 
and elsewhere, on rocks, and the roots of Cedars, in Southern Massa- 
chusetts (Ir. Willey) in Rhode Island (Mr. J. L. Bennett) and in New 
York (Mr. C. H. Peck). With this species we complete our list, as itnow 
stands, of Biatore with simple spores.' There isan obvious conrenience, 
in the present place, in considering it apart, and in permitting also the 
successive modifications of the originally simple spore, as this gradually 
accomplishes the evolution of its type, to determine the remaining 
groups: but the sundering of natural affinities which is thus made neces- 
sary, invalidates the arrangement ; and Nylander has refused to recognize 
it at all. B. vernalis (as here understood) B. cyrtella, B. spheroides, and 
B. rubella are types of these structural differences, as of the genera of 
Biatorei supposed to be predicable upon them; but the lichens named 
are members also of a single group of species, which, whether or not we 
sunder, Nature keeps together. 
In the immediately following little cluster of Biatore, fuller expression 
is given to the indications afforded by the last of bilocular modification ; 
and—excluding some forms possibly referable elsewhere, as Biatorina 
pyracea, Massal., to Placodium, and B. pineti and B. lutea, Koerb., to 
Gyalecta — the group is identical with Biatorina of recent.authors. Bia- 
tora cyrtella (Ach.) in its blackening, convex condition (Vermont, Messrs. 
Frost and Russell; White Mountains) which is referred here by Dr. 
Nylander, is distinguishable, and the spores, though commonly simple, 
become at length bilocular and a little oblique; but paler-fruited states 
(Vermont, Mr. Frost) even though often more frequently bilocular, are 
perhaps also conceivable as a corticoline expression of B. vernalis —— 
B. globulosa (Floerk.) is determined by his #xs.; the B. anomala, Fr., 
' Many interesting forms are doubtless yet to be added. B. mutabilis (Fée) is 
a native of Mexico (Nyl. Enum.) and is possibly represented by a Louisiana lichen 
(Hale) agreeing exactly with a Brazilian one (Herb. Kunz.) referred by the late 
Dr.-Meissner to B. mixta, Fr. It is probable that what is now called B. atropur- 
purea was intended in this reference; and both the Brazilian and Louisianian 
specimens are well-comparable with the first-named, except indeed that the similar 
spores appear always to be simple. Other tropical species probably extend farther 
north; and the Cuban lichens of the present group, among which, beside others 
already named, are B. oncodes, B. orphnea, B. furfurosa, B. polycampia (Lecidea, 
Tuck. Obs. Lich., & in Wright Lich. Cub.) may, some of them, be found in Florida. 
