LICHENS OF THE STATE OF WASHINGTON 51 



veins, rhizoids scarce. Apothecia 3.0-5.0 mm. across, round to oblong, 

 revolute, borne on the tips of short digitately clustered lobules, adnate ; disk 

 reddish brown ; proper margin irregularly crenulate ; asci 8-spored ; spores 

 hyaline, acicular, slightly curved, 3-7-septate, 22.9-75.9 x 2.6-5.0 ^i. 



On soil and mossy rocks: Island Co.: Whidbey Island, 1931, 1776. 

 Mason Co.: Shelton, 1931, 1225. Kitsap Co.: Hidden Ranch near Bremer- 

 ton, 213 ft., 1930, 1854. Pierce Co.: Mt. Rainier, trail to Mowich Lake, 

 3500 ft., 1940, 3062. San Juan Co. : Orcas Island, Olga, 1906, Fink 347 

 (W). 



This species resembles P. venosa somewhat in the small size and shape 

 of the thallus, but the revolute apothecia easily separate it from that species. 



17. LECIDEACEAE 



Thallus crustose or squamulose, sometimes marginally lobed, dififeren- 

 tiated into definite cortical, algal, and medulla layers, or in some genera 

 showing little dififerentiation ; attached to the substratum by hyphal rhizoids. 

 Apothecia circular, scattered, adnate, sessile or rarely stipitate ; proper mar- 

 gin well developed, thalline margin absent ; asci usually 8-spored, sometimes 

 16-30-spored ; spores hyahne or brown, nonseptate, 2-many-septate, or 

 muriform. 



Alga Protococciis or Gloeocapsa. 



A. Spores nonseptate. 



B. Spores very large, thick walled 32. Mycoblasttis 



B. Spores not very large, thin walled 31. Lecidea 



A. Spores septate. 



C. Spores 1-many transversely septate. 



D. Spores 1-septate 33. Catillaria 



D. Spores 2-many-septate. 



E. Thallus non-corticate, crustose 34. Bacidia 



E. Thallus corticate, squamulose 35. Toninia 



C. Spores muriform, rarely only transversely septate. 



F. Spores hyaline 36. Lopadiiim 



F. Spores normally brown, rarely hyaline. 37. Rhisocarpon 



31. Lecidea Ach. Meth. Lich. 32. 1803. 



Thallus crustose, granulose, areolate, or squamulose, often lobate at the 

 margin, sometimes bearing soredia or cephalodia, with a typical pseudo- 

 parenchymous upper cortex or one of closely packed liyphae, distinct algal 

 and medullary layers, and a lower cortex absent or poorly developed ; in 

 some genera there is no differentiation into definite layers. Apothecia usually 

 circular, sometimes angulate, adnate or sessile ; proper margin concolorous 

 with the disk, often disappearing ; hypothecium hyaline, brown, or almost 

 black; paraphyses rarely branched, sometimes forked near the apex, the 

 amount of coherence is variable; asci usually 8-spored, rarely 16-spored; 



