SAPROPHYTIC FUNGI OF EASTERN IOWA. 



17 



villous, white, azonate at tirst smooth, then concentrically sul- 

 cate; margin entire, acute; pores quite large, pallid, acute then 

 lacerate-dentate. 



Specimens doubtfully here referred are obsoletely zonate at 

 first, are inclined to be scutate-attached, are less fibrous than 

 is to be expected. Our form may prove to be a Trametes. 

 Entered provisionally. 



8. PoLVSTicTUs coxcHiFER Schzvciiiitz . 



Small, thin, spongy-coriaceous, white; pileus conchiform, 

 very smooth, shining; pores medium, dentate. 



This is a very curious, very variable but very common little 

 species. Immediately recognized by its shape which recalls 

 that of a Peziza mounted on a short base-like pedicel. 

 Smaller specimens are crucible-like and remind one of the 

 little cups of Cnicibiihiiu. Larger specimens (2 cm) are more 

 or less whorled or helicoid, or spirally imbricate from a com- 

 mon central base, shading off toward forms of P. versicolor. 

 In color alutaceous, pallid or white, always marked by several 

 handsome, concentric, fuscous zones. The hvmenium is yel- 

 lowish; pores large with thin dissepiments. 



Very common on dead branches of Uhniis aincn'caiia, but 

 perishing after the twig falls to the ground. P, virginciis, of 

 the same author, is here included. Pileus 1-2 cm. N. A. F. 

 1303- 



X. FOMES. 



Pileus from the outset woody-indurate (rarely soft), with a 

 floccose interwoven context, covered by a rigid crust, azonate 

 but at length concentrically sulcate, perennial, producing suc- 

 cessively new strata; reviving in ever}- case by the activity of 

 the stratum latest formed. 



I. FoMEs RENiFORMis MorsTau. 



Pileus sessile or substipitate, reniform or dimidiate, ascend- 

 ing, concave above and convex below, concentricallv sulcate 

 and subzonate; the margin thin and acute. Pores minute, 

 ferruginou>, the mouth whitish. 



