134. Gyrophora] 35. GYROPHORACEAE 271 



the exciple thin, brown, soon disappearing; spores acicular, 3-septate, 22-35 X 

 2-3.5 //.. 



On soil over rocks, throughout northern United States, and in New Mexico. 



var. simplex Riddle, Bot. Gaz. 50:298. 1910. 

 Podetia elongated, slender, sparingly branched, the squamules more or less 

 scattered; apothecia rarely terminal. 



On sandy soil, Washington and Oregon. 



7. Stereocaulon alpinum Laurer, in Funck, Crypt. Gewachse 33. Heft. 6. 1827. 



S. tomentosum var. alpinum (Laurer) T. Fries. 



Podetia short, stout, erect or decumbent, clustered, becoming branched, the 

 branches thinly tomentose, squamulose, the squamules small, ashy to whitish or 

 brownish, becoming warty and conglomerate or passing into minute, coralloid 

 branchlets ; apothecia small to middle-sized, 0.6-2 mm. across, terminal or rarely 

 lateral, the disk flat to convex, reddish brown to brownish black, the exciple thin, 

 colored like the disk, commonly disappearing; spores acicular, 3-septate, 20-35 X 

 2.5-4.5 (i. 



On rocks, Maine, New Hampshire, Minnesota, Wyoming, Washington, and 

 Oregon. 



var. botryosum (Ach.) Laurer, in E. Fries, Lich. Eur. 204. 1831. 



S.botryosum Ach., in Lam. & DC, Fl. Franc, ed. 3. 6:178. 1805. S. tomen- 

 tosum var. botryosum (Ach.) Nyl. 



Podetia densely clustered, much branched, the branches smooth below, 

 densely squamulose above, the squamules small, ashy gray to brownish, passing 

 into minute, warty, or conglomerate granules. 



On rocks, Maine. 



8. Stereocaulon denudatum Floerke, Deutsch. Lich. part 4. 13. 1819. 

 S. glaucescens Tuck. 



Podetia short to moderately long, erect or ascending, slender, loosely or 

 sometimes densely clustered, becoming much branched, the branches smooth, 

 squamulose above, the squamules grayish white to brownish, passing into mi- 

 nute, irregular, confluent granules; apothecia small, 0.3-0.7 mm. across, lateral 

 or sometimes terminal, rarely clustered, the disk flat to slightly convex, brown- 

 ish black to black; spores acicular, 3-septate, 22-40 X 2.5-4 /x. 



On soil, New England, New York, New Jersey, Pennsylvania, Minnesota, 

 Washington, and California. 



OTHER SPECIES REPORTED 

 Stereocaulon chlorellum Tuck. — North America. 

 Stereocaulon ramulosum (Swartz) Ach. — Oregon. 



35. GYROPHORACEAE 



Thallus distinctly foliose, differentiated into well-developed plectenchyma- 

 tous cortices, algal and spongy medullary' layers, attached to the substratum by 

 an umbilicus; apothecia round, scattered, sessile to shortly pedicellate, the disk 

 grooved, giving the appearance of a compound apothecium, the proper exciple 

 wanting or more or less developed, sometimes surrounded by a thalloid one. 



The algal host is Pleurococcus. 



A. Spores non-septate 134. Gyrophora 



A. Spores septate 



B. Spores transversely septate 136. Dermatiscum 



B. Spores transversely and longitudinally septate 135. Umbilicaria 



134. Gyrophora Ach., Meth. Lich. 100. pi. 2, f. 6. 1803. 



Thallus foliose, attached by an umbilicus, the margin entire to variously 

 lobed and torn, having a strongly developed plectenchymatous cortex above 



