GENERA AND SPECIES. 141 



rhizoids sparingly present and black. Apothecia nu- 

 naerous, medium to large, cup-shaped, margin incurved, 

 crenate. Disk dark-brown. Spores brown, typical, 

 36/x, X 17/x. 



10. Physcia speciosa. Thallus branched, lobes strap- 

 shaped, bearing a few cilia, usually lying close, but 

 only loosely attached to the substratum, greenish-gray 

 above, lighter color beneath with comparatively few 

 dark rhizoids. Apothecia medium to large, cup-shaped, 

 crenulate margin curved inward. Spores brown, 

 typical, 21/x X Hfi* 



11. Physcia comosa. Thallus branched from two 

 to about six times, lobes ascending and of quite uni- 

 form width ; numerous, long, slender, dark cilia from 

 the margin, rarely from the upper surface of the thal- 

 lus as well ; uniform, pale ash-gray above, paler below, 

 no rhizoids. Apothecia terminal, margin extending 

 considerably above the gray disk. Spores brown, 

 11 fx X 34/.. 



12. Physcia hispida. Thallus much as in P. co- 

 mosa but with lobes inflated at the tips, cilia usually 

 more slender and numerous. Apothecia medium, mar- 

 gin only slightly raised above disk. Disk gray to 

 nearly black. Spores brown, 20.5/i, X ll/>t- 



13. Physcia ciUaris. Thallus much branched, lobes 

 linear, somewhat ascending, branches terminating in 

 long slender cilia, which are usually darker than the 

 lobes; ash-colored to dark-brown above, nearly the 

 same color beneath, no rhizoids. Apothecia rare, me- 

 dium, cup-shaped, bearing some short cilia. Disk 

 brown to dark. Spores dark-brown, 35/x X 17/a. 



