POLYPOBUS. SISTOTBEMA 591 



1962. P. chioneus Fr. Pers. Myc. Eur. n, 1. 15, figs. 4, 5. xidav, snow. 

 P. 2-5 cm., white, dimidiate, sometimes constricted behind into a 



stem-like base, becoming even, smooth; margin inflexed, thin, acute. 

 Tubes white, short; orifice of pores white, minute, round, becoming 

 toothed with age. Flesh white, soft, watery, then rigid. Spores 

 white, "elliptical oblong, 5 /A, incurved" Quel. Taste astringent. 

 Birch stumps, and fallen branches. June Dec. Uncommon, (v.v.) 



1963. P. pallescens Fr. Pallescens, growing pale. 

 P. 4-7-5 cm., yellowish, dimidiate, subcaespitose, even, smooth; 



margin acute. Tubes white, short; orifice of pores white, becoming 

 yellowish, minute, round. Flesh yellowish, soft, then corky. Spores 

 "ellipsoid, 6-8 x 4/i" Sacc. Old stumps. Bare. 



1964. P. albidus Trog. Schaeff. Icon. t. 124. AlUdus, whitish. 

 P. 6-10 cm., white, globose, shell-shaped, triquetrous, or sub- 



applanate, sometimes slightly stalked, dry, dull smooth. Tubes white, 

 short; orifice of pores white, round, at length sinuate and splitting. 

 Flesh white, hard, corky- woody. Spores white, elliptical, 5-6 x 3-4 JJL. 

 Abies. Sept. Oct. Rare, (v.v.) 



1965. P. cerebrums B. & Br. Cerebrinus, brain-like. 

 P. 2-5 cm., snow white, pulvinate, resupinate, delicately tomentose, 



becoming smooth; margin crenate. Tubes and orifice of pores white, 

 rather large, round, entire, smooth. Flesh white, 6 mm. thick. Spores 

 "white, subfusiform, 5 x 2-5 /z" Massee. Fir. Aug. Rare. 



Sistotrema (Pers.) Fr. 

 (cmo-ro?, shaking; rprjfjua, a hole.) 



Pileus fleshy, hemispherical, spathulate, effuso-reflexed, or resupi- 

 nate. Stem central, lateral, or none. Tubes becoming broken up into 

 teeth, or plates, and anastomosing at the base. Flesh pale, or coloured. 

 Spores white, subglobose, oboval, or oblong; smooth, or echinulate; 

 basidia with 4-8-sterigmata. Cystidia none. Growing on the ground, 

 or on wood. 



1966. S. confluens (Pers.) Fr. Boud. Icon. t. 169. 



Confluens, confluent. 



P. 1-2-5 cm., white, then yellowish, hemispherical, spathulate, or 

 irregular, horizontal, villose; margin often yellowish, flexuose. St. 

 5-2-5 cm. x 2-3 mm., white, or ochraceous, central, or lateral, often 

 connate, attenuated downwards, pruinose. Tubes concolorous, be- 

 coming broken up into teeth, or plates, flexuose, entire, or toothed, 

 pruinose. Flesh white, often yellowish at the base of the teeth, thin, firm. 

 Spores white, oval, subglobose, 4-5 x 3-4/u,, 1-multi-guttulate. 

 Coniferous woods. Sept. Nov. Not uncommon, (v.v.) 



