THE POLYPORACEAE OF WISCONSIN. 61 



iments, at length torn and wavy, sometimes becoming oblique. They 

 are of the same color as the stipe. Dimensions of largest specimen 12 

 cm. in diameter; stipe 4cm. long, flesh about 2 mm. thick. 



This species is related to P. subsericeus Peck, from which it is dis- 

 tinguished by its coarser and larger structure as well as its duller pi- 

 leus. 



§2. Discipedes. Clustered, stipe short, scutate-dilated at base, sub- 

 reniform or spatulate, coriaceous. 



Polystictus conchifer Schw. (Plate IV, fig. 20). 



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

 smooth, shining ; pores medium, dentate. 



Young specimens are quite common in autumn on fallen twigs, es- 

 pecially those of elm. Older and mature specimens are not so com- 

 mon. A few of the latter have been collected at Horicon, Madison, 

 Bangor, Hazelhurst, Crandon. The largest of these is about 4 cm. 

 wide, 3 cm. long and from 1 — 4 mm. thick. They are mostly dimidiate 

 or flabelliform, a few are scarcely substipitate. The margin is very 

 acute, either smooth and rounded or lobed and wavy. The pileus is 

 smooth, or it may in some cases be roughened by scales or tubercles ; it 

 is often radiately rugose and has narrow concentric suications. The 

 base is usually more or less thickened and narrowed. 



The color varies from white to pale-tawny or straw-color. The flesh 

 is thin, soft, somewhat fibrous, white. The pores are hardly medium 

 in size, equal, irregular, of the same color as the pileus. The dissepi- 

 ments are thin and slightly dentate. The length of the tubes is near- 

 ly twice the thickness of the pileus — averaging about 2 — 2.5 mm. 



The mature specimens are very different from the young ones. 

 These usually arise in the form of small cup or saucer-shaped bodies — 

 with a longer or shorter stipe, or wholly sessile ; resembling in various 

 stages small Pezizas or Thelephoras. Within, the cups or saucers are 

 dark brown with more or less shining zones or bands. These bands 

 soon fade when exposed to the weather, if the specimen is dead, and the 

 plant becomes a lusterless grayish-white. At the saucer-stage the 

 pores first make their appearance on the outside under the rim. Then 

 the lower edge of the saucer grows out into a pileus. The saucer may 

 persist in its entirety, or in part ; it may break up and the fragments 

 be distributed over the surface of the pileus as tubercles or scales ; it 

 may simply leave a depression, or it may disappear entirely. 



