FINK—THE LICHENS OF MINNESOTA. 1438 
laria, which is quite gelatinous when wet. The algal symbiont is Gloeocapsa-like, 
and the gelatinous nature of the Omphalarias is due to the sheath of the cells or the 
colonies. There is an obscure differentiation into algal and medullary layers in the 
Omphalarias. 
The apothecia are usually immersed and contain the simple or 2-celled spores, 
which are quite similar in the two genera and suggest a close relationship of their 
members, though these are quite different externally. 
‘The family is somewhat closely related to the Collemaceae, and the relationship 
with the Pannariaceae is perhaps closer. 
PYRENOPSIS Nyl. Mém. Soc. Sci. Nat. Cherb. 5: 143. 1857. 
The thallus is crustose-conglomerate or with ascending coralloid branchlets. The 
whole structure is obscure and devoid of definite layers. However, in ours at least, 
a parenchymatous structure may be made out, which extends throughout, at least — 
in the ascending branchlets. The algal symbiont consists of blue-green cells, occur- 
ring in clusters, varying considerably in size and number in a cluster and the indi- 
vidual cells not differing greatly from those of Omphalaria. The plants are obscure, 
and when conspicuous enough to attract notice, they may easily be overlooked as 
so much dirt on the rocks, or if noted as lichens, passed over as some one of the darker 
and more obscure Pannarias. The apothecia in ours are usually quite open-discoid, 
and yet they are rather rare, adnate or immersed, small and very difficult to distin- 
guish when present. A thalloid exciple is present. The hymenium and the hypo- 
thecium are both more or less brownish. The paraphyses are usually simple and 
rather slender, but not seldom more or less gelatinized and indistinct. The spores 
are almost constantly simple. 
Nylander recognizes Synalissa Fr.¢as a separate genus, somewhat below the present 
one in that the thallus is scarcely cellular and the apothecia are more inclined to be 
immersed. He admits to his lower genus, however, at least one form having a cel- 
lular thallus. Tuckerman admits all these species to the present genus and also 
certain species having the algal cells in chains. Much work will be required before 
the questions involved can be settled, but our three species may certainly be 
placed in a single genus. Again, while there is yet much doubt regarding the rela- 
tionship of some of the species usually assigned to the present genus and Synalissa, it 
appears to be certain enough that ours are more closely related to Pannaria than to 
Collema, and are yet nearer to Omphalaria. 
Three species occur in the State. On rocks. 
Type species Pyrenopsis fuscatula Nyl. loc, cit. 
KEY TO THE SPECIES. 
Thallus olivaceous, granulose; spores 8 to 11 » long and 5 to 6 4 
Wide. ... 2.2... 2.222 eee eee eee eee eee eee eee eee 1. P. melambola. 
Thallus blackish, granulose. 
Spores 10 to 20 » long and 7 to 9 » wide, sometimes 2-celled. 2. P. phaeococca, 
Spores 12 to 13 » long and 6 to 8 » wide..............----- 3. P. polycocca, 
1. Pyrenopsis melambola Tuck. Syn. N. A. Lich. 1: 136. 1882. 
Synalissa melambola Tuck. Proc. Amer, Acad. 12: 170. 1877. 
Thallus of minute olivaceous granules, compacted into finally thick and substipitate 
scabrous, black areoles, these reaching 1 mm. in diameter and forming a close crust; 
apothecia minute, 0.2 to 0.4 mm. in diameter, 1 to 6 in each areole, immersed, 
the disk black, the margin thalloid, persistent, and of the same color as the disk; 
hypothecium pale brownish; hymenium usually pale below and pale brownish 
aSyst. Orb. Veg. 1: 297. 1825. 
