62 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 
spores 8, ovoid and broadly ellipsoid, colorless to decolorate, 20 to 28 » long, 14 to 20 p» 
thick; hymenial gelatine with iodine blue, the spores yellow. 
On bowlders near Tehachapi Station at 1,300 meters altitude; at Camp Baldy, 
San Antonio Canyon, in the San Gabriel Range at 1,500 meters. 
ACAROSPORACEAE. 
Thallus crustaceous, squamous, or foliaceous, often scantily developed; gonidia 
Protococcus or Pleurococcus; apothecia imbedded in the thalline squame, sessile or 
subpedicellate; disk circular, often narrowed or irregular, lecideine, biatorine, or 
lecanorine; asci multisporous; spores simple, commonly ellipsoid, rarely globular, 
colorless; spermatia oblong-ellipsoid, on a subsimple sterigma. 
KEY TO GENERA, 
Apothecia with a proper margin, biatorine or lecideine... BraTORELLA (p. 62). 
Apothecia lecanorine...............-2. 0000 eee eee eee eee f ACAROSPORA (p. 63). 
BIATORELLA De Not. 
Thallus crustaceous, uniform or subefligurate at the circumference or obsolete; 
apothecia biatorine or lecideine, the proper margin devoid of thallus, with Pleurococ- 
cus gonidia, the apothecia innate, sessile or subpedicellate, circular. 
KEY TO SPECIES. 
Substratum bark or wood..........---..--------2-e-0-e0e- ...-. 4. B. moriformis. 
Substratum rock. 
Thalluse effuse, indistinct...................-. eee eee eee eee 5. B. hypophaea. 
Thallus obsolete. 
Apothecia stipitate...................2.- 22 eee eee eee ee eee 3. B. clavus. 
Apothecia, sessile. 
Disk pruinose, black...........--.-.---.---++------ 1. B. pruinosa, 
Disk not pruinose, black............-.-.---.--------- 2. B. simplex. 
1. Biatorella pruinosa (J. E. Smith) Mudd. 
Thallus obsolete or a few inconspicuous granules clustered around the apothecia; 
apothecia adnate, clustered or dispersed, 0.25 to 0.5 mm. in width; disk flat, dull 
black, pruinose (blackening when moist) with a permanent, thin, regular or wavy, 
concolorous margin; epithecium dark brown, continuous; thecium colorless, 56 to 
60 » high; paraphyses free, adglutinated only at the apices, scarcely thickened above, 
the tips pale brownish; hypothecium pallid amber yellow; asci oblong-ellipsoid, 
thickened above, about equaling the thecium in height; spores minute and numerous, 
3 to 4 p long, barely 1 » thick; hymenial gelatine with iodine sordid greenish blue, 
the thecium and hypothecium blue and of darker shade than the thecium, the ascus 
wall not stained, but its contents yellow. 
On quartzose and other rocks. Sandstone in the Santa Cruz Mountains, Herre; 
frequent on quartz in the Santa Monica Mountains; in the San Bernardino Mountains, 
Parish. 
An epruinose state (forma nuda Nyl.) is found occasionally with the species, the 
apothecia barely or not at all pruinose, sessile, somewhat larger than in the species, 
the disk convex with a persistent, concolorous margin, the thecium 80 to 100 » high, 
colorless, the spores 4 to 5 # long, about 1 » thick. 
2. Biatorella simplex (Davies) Branth & Rostr. 
Thallus absent; apothecia sessile, 1 mm. or less wide, disk dark brown black, round 
or angular, turgid-papillate, surrounded by a concolorous, similarly turgid and inter- 
