THE LICHEN-FLORA OF CHICAGO AND VICINITY. 23 



31. P, rufescens, (Neck.) Hoffm. Thallus large, coriaceous, rotund, 

 lobate, lobes elevated and crisp, ash colored to reddish-brown; 

 beneath reticulated with brown veins, fibrillose; apothecia on 

 lobules, large; disk revolute, rufo fuscous. Spores acicular. 

 Fr. L. E. 46. Tuck. exs. n. 104. Calkins, exs. 



Occurs at Glencoe in ravines and on hillsides, on earth and old 

 mossy logs. Found also at River Forest near ihe Desplaines 

 River and throughout our territory. * Tuckerman says this 

 species stands in embarrassing relations to P. canina. 



FAMILY 4. PANNARIEI. 



Heppia, Naeg, Thallus squamose-foliaceous, monophyllous, Goni- 

 mous layer of gonimia; apothecia round, immersed. Spores 

 ovoid. 



32. H, despreauxii, (Mont.) Tuckerm. Thallus small, round, 

 smooth, or regulose, green; apothecia separate, or in roset- 

 tes, sunken in thallus, disk reddish or salmon-colored. 

 Found on calcareous earth near Lemont. This curious lichen 



being very small is not easily seen. It seems always to be 

 associated with Endocarpon hepaticum in habitat, and has 

 often been mistaken for a fungus. 



Pannaria, Delis, Thallus squamulose, subfoliaceous or mono- 

 phyllous, the h3^pothallus spongy or obsolete; apothecia 

 scutellaeform, with both thalline and proper margins, frequently 

 biatorinc. Gonimous layer of both gonidia and gonimia. 



33. P, nigra, (Huds. ) Nyl. Thallus squamulose, minute, lead 

 colored, and mostly merged into a granuloid crust; apothecia 

 small, biatorine, sessile; disk black, margin entire. 



On calcarieous rocks near Lemont and in Will County. 



FAMILY 5. COLLEMEI. 



Collema, (Hoffm.) Fr. Thallus greenish, cortical layer obsolete; 

 gonimia in chains; apothecia very small to middle size; 

 scutellaeform. Spores variously shaped. 



* other species of this genius are likely to oeeur. 



