CALDESIELLA SISTOTREMA IRPEX. 167 



SISTOTPcEMA. Pers. (figs. 4, 5, p. 149.) 



Fleshy. Hymenium inferior, interruptedly lamelloso- 

 dentate, rather waxy, irregularly scattered (not radiating), 

 readily separating from the pileus. Basidia tetrasporous. 



Sistotrema, Persoon, Syst. Myc. i. p. 426; Cke., Hdbk., 

 p. 302. 



Allied to Irpex, but distinguished by the irregularly- 

 toothed gills disposed without order, and readily separating 

 from the pileus. 



Sistotrema confluens. Pers. (figs. 4, 5, p. 149.) 

 Pileus fleshy, irregular, horizontal, villous, white, then 

 yellowish or tinged with brown, subdepressed, ~1 in. 

 across, several pilei often grown together ; gill-like plates 

 entire or toothed; stem about 1 in. high, often somewhat 

 excentric, becoming thinner downwards ; spores colourless, 

 elliptical, 3 x 1 * 5 p 



Sistotrema confluens, Persoon, Syn. Fung., p. 551 ; Cke., 

 Hdbk., p. 302. 



On the ground. Gregarious, often anastomosing or two or 

 three growing into each other, scentless, brittle, whitish, at 

 length yellowish or tinged with brown. Stem attenuated 

 below, central or lateral, about an inch high. Pileus about 

 1 in. broad, somewhat depressed. Tooth-like plates of the 

 hymenium entire or jagged. (Grev.) 



IRPEX. Fr. (figs. 6, 7, p. 149.) 



Hymenium inferior, toothed from the first, teeth con- 

 tinuous with the pileus, acute, smooth, connected at the base 

 by slightly-raised folds arranged in a gill-like manner (in 

 sessile species), or like honeycomb (in resupinate species). 

 Basidia tetrasporous. 



Irpex, Fries, Blench., 142 ; Stev., Fung., p. 248. 



Distinguished from Hydnum by having the spines con- 

 nected at the base. The spines in the present genus also 

 differ from those of Hydnum in not being so uniformly awl- 

 shaped or cylindrical, with a tapering pointed tip. 



Hymenium inferior, at first toothed, teeth variable, firm, 



