108 GUIDE TO THE STUDY OF LICHENS. 



sisting of numerous raiuute but distinct elevated gran- 

 ules, whitish to yellowish-green. Apothecia medium 

 size. Disk convex, bright-scarlet. Spores oblong, 

 often somewhat larger at one end, simple, colorless. 

 24/x X 4/x. 



This species does not occur in the northeastern 

 United States. It is western and southern in its 

 range. 



Jf. Bilimhia. 



This is another insignificant group represented by 

 only a few species. Its general characters correspond to 

 those of the Biatoras and Lecideas. Various authors 

 include it under Biatora. 



The thallus is crustose, never becoming foliose as in 

 some of the Biatoras. The apothecia are of medium 

 size. Disk flattened or convex, color yellowish-brown 

 to dark-brown. The algse are in all probability Proto- 

 coccus, but differ from the usual forms in their small 

 size. Spores are spindle-shaped, colorless, usually 

 four-celled. 



The Bilimhias occur upon tree-trunks and moss. 



1. Bilimhia mixta. Thallus granular, warty, whitish, 

 or faintly yellow. Apothecia small, adnate. Disk 

 convex, usually black. Spores oblong, two to four- 

 celled, colorless, sometimes slightly curved, 18/i, X 5/x. 



2. Bilimhia hypnophila. Thallus granular, spread- 

 ing, greenish to gray. Apothecia small, sessile, un- 

 evenly convex. Disk black, thecium and hypothecium 

 reddish-brown. Spores as in B. mixta. 



3. Bilimhia sphceroides. Thallus distinct, uniformly 

 spreading, granular, greenish, Apothecia nearly glo- 



