66 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 
Collected at Warroad and Tower. On cedars. A rare lichen in the State and 
also for North America. 
Known elsewhere in North America in Massachusetts and Washington, and at 
Lake Manitoba and Lake Winnepegosis. Known also in Europe. 
Biatora moriformis of the preliminary reports. 
2. Biatorella simplex (Dav.) Br. & Rostr. Bot. Tidssk. 3: 241. 1869. 
Lichen simplex Dav. Trans. Linn. Soc. Lond. 2: 283. pl. 28. f. 2. 1794. 
Thallus deficient and seldom seen; apothecia small or minute, 0.2 to 0.8 mm. in 
diameter, adnate, scattered or crowded into dense clumps, rounded or becoming vari- 
ously irregular, the disk dark red or black, the thin exciple persistent, raised and black; 
hypothecium cloudy or brownish; hymenium pale; paraphyses slender, simple or 
rarely branched, frequently somewhat thickened and brownish toward the apex; 
asci cylindrical or cylindrico-clavate; spores oblong-ellipsoid, minute, 3 to 5 » long 
and | to 1.5 ~ wide, very numerous in the asci. 
Found in the southern half of the State wherever limestone occurs and as far to the 
northwest as Leaf Hills and Battle Lake. On limestones. 
Widely distributed in the United States and as far north as Newfoundland. Known 
in all of the grand divisions except South America. 
Lecanora privigna is the synonym of the preliminary reports. 
2a. Biatorella simplex pruinosa (J. E. Smith) Fink. 
Lichen pruinosus J. E. Smith in Sowerby, Engl. Bot. 82: pl. 2244. 1811. 
Thallus thin and perhaps as deficient as in the last; apothecia more closely appressed 
or even more or less immersed in the substratum, the disk more or less pruinose, be- 
coming rather larger, reaching | millimeter or more in diameter, otherwise externally 
and internally as the above. 
Sometimes considered a distinct species, but certainly connected by intermediate 
forms with the B. simplex. 
Occurring with the type and on the same substrata. 
North American distribution about as of the last, but not found quite so far north. 
Found also in Europe and Africa. 
Lecanora privigna pruinosa of the preliminary reports. 
3. Biatorella clavus (Lam. & DC.) Th. Fr. Lich. Scand. 2: 409. 1874. 
Patellaria clavus Lam. & DC. FI. Fr. ed. 8. 2: 348. 1805. 
Thallus as in the last, but perhaps more commonly present though indistinct; apothe, 
cia middle-sized or larger, 0.7 to 2 mm, in diameter, rather loosely sessile or substipi- 
tate, scattered or somewhat clustered, rounded or becoming wavy or variously irregu- 
lar, the disk dark red or black, concave or becoming flat or even somewhat convex, 
the exciple thick, chinky and raised, or finally disappearing; hypothecium brown 
or blackening; hymenium pale or brownish; paraphyses simple or rarely branched, 
scarcely so slender as in the last, commonly enlarged and brownish or bluish toward 
the apex; asci cylindrico-clavate or ventricose; spores oblong-ellipsoid, minute, 4 to 
6.5 » long and 2 » wide, thus on the whole larger than those of the last. 
Sometimes considered a subspecies of the last, but ours seems distinct enough, as 
does all other material at hand. 
The plant was collected on the sandstone at MacGregor, Iowa, and no doubt occurs 
on the same rocks along the Mississippi River in Minnesota. 
Elsewhere in North America known from New England, West Virginia, Georgia, 
Kansas, and California. Known also in Europe. 
