254 HERRE 



On various trees in the foothills and also on rocks and old fences. 

 Of world wide distribution. 



Differs from sophodes in the reduced, effuse thallus and smaller 

 spores, while the hypothallus is indistinct or absent. 



PHYSCIACEJE. 



Thallus usually foliaceous, stellate, or orbicular, appressed, la- 

 ciniately branched orlobed; rarely fruticose or ascendant; beneath 

 fibrillose, or more seldom naked; cortical layer present; alga Protococ- 

 cus. 



Apothecia usually abundant, shield-shaped, lecideine or lecano- 

 rine; the disk dark or blackish, often pruinose; paraphyses simple; 

 asci with 8 brown, ellipsoid, in our species, bilocular and thick- walled 

 spores. 



KEY TO THE GENERA. 



A. Upper cortical layer of pseudoparenchyma, formed of hy- 



phae perpendicular to the surface LXIII. Physcia 



A A. Upper cortical layer of longitudinal hyphae, not forming 



pseudoparenchyma LXIV. Anaptychia 



LXIII. Physcia (Schreb.) Wainio. 



Physcia Schreber, Genera Plant. 2: 767. 1791, in part. 

 Physcia Wainio, Etud. Lich. Bresil, 1 : 138. 1890. 



Thallus foliaceous, stellate or orbicular, appressed or ascendant, 

 usually attached by rhizoids, laciniately branched or lobed; lobes 

 dorsi- ventral, both sides with cortical layer; medulla cottony, white, 

 saffron, sulfur-colored, or red. 



Apothecia shield-shaped, sessile, with thalline margin; disk dark 

 to black, often pruinose; paraphyses simple, septate, rarely unsep- 

 tate; epithecium not affected by KOH; hypothecium colorless or 

 dark; spores 8, brown, ellipsoid, thick- walled, bilocular, rarely quad- 

 rilocular or muriform through the interpolation of longitudinal 

 septa. 



This widely distributed genus is well represented with us. 



KEY TO THE SPECIES. 



A . Thallus more or less pruinose. 



B. Thallus silvery white 2. pulverulenta argyphaa. 



BB. Thallus more or less brown. 



