tort] HERRE—DESERT LICHENS 289 
species, but I place it here for lack of further material for compari- 
son, and because as yet the abundant apothecia have not yielded 
me spores. 
g. LECIDEA TESSELATA Floerke. 
10. LECIDEA AURICULATA DIDUCENS Th. Fr. 
11. LECIDEA scotopHotis (Tuck.) Herre—A doubt is cast 
upon this determination because of the small spores. A specimen 
from California, determined by TUCKERMAN, gives spores ee Bs 
while the Reno specimens have spores measuring but —— o 
12. Lecidea truckeei Herre, n. sp.—Thallus indeterminate, 
apparently of medium-sized, rigid, leafy, thickish scales which are 
ensely crowded, ascendant or imbricate, with entire or crenate 
margin. On removing a single plant it is seen to be peltate, pro- 
longed downward into a stout irregular stem, and with a broad 
top (4~10 mm. wide) of imbricate lobules, which form the scales 
of the thallus as seen from above; the lobules usually concave or 
undulate, less often revolute, their upper surface characteristically 
finely reticulate and wrinkled to form convex areolae; color dull 
chestnut brown or yellow brown; under side of the lobules black, 
the stems a dusky ashen; medulla bluish or purplish with I; thallus 
dusky olive with KOH+CaCl,0.. 
Apothecia small, usually numerous, black; at first very small 
and flat, with a thin, rather entire and slightly lighter-colored 
Margin; becoming convex as they get larger, and more or less 
excluding the margin; sometimes they are conglomerate or clus- 
tered and irregular; epithecium greenish black; hypothecium 
brown or brownish; paraphyses confluent or agglutinate, slender, 
threadlike; thecium greenish pale, turning blue with I; the ven- 
tricose fertile asci are rare; spores globose, 4.66 to 7 # in diameter. 
n rhyolite, 2 miles north of Reno, at an altitude of 5000 feet, forming 
fonspicuous patches several inches broad. Though bearing a superficial 
resemblance to an unusually luxuriant form of Lecidea atro-brunnea or some 
forms of Lecidea slobifera, it is markedly different in both thallus and spores, 
13. Bactpra TRISEPTA (Naeg.) A. Zahlbr. (?) or BACIDIA LECIDI- 
OIDES (Anzi) (?)—Determination uncertain for lack of properly 
