LEUCOSPORI. 167 



lique, rather plane ; flesh thick. Stem very curt and obese, com- Pleurotus. 



monly 2.5 cent, (i in.) long and thick, somewhat lateral, somewhat 



woody, squamulose, white, with a short, blunt root. Veil scarcely 



conspicuous on the stem, but appendiculate round the margin of 



the pileus when young. Gills not very decurrent, soineivat simple, 



not anastomosing behind, narrow, white, becoming yellow when 



old. 



The veil is almost that ol A. coi-ticahis. The flesh is the same but thicker, 

 and not so much thinned out towards the margin. The gills are narrower 

 and less distant, but both agree in the gills becoming yellow when old. In 

 reality it is allied to A. corticaHis, but the stem is definitely lateral ; other- 

 wise smaller, harder and mo?'e brawny. 



On trunks, oak, ash, willow^, &c. Uncommon. Sept.-Oct. 



Pileus 18 mm.-7.5 cent. (^-3 in.) broad, margin involute. Stem 7.5 cent. 

 (3 in.) high (in my specimens elongated from growing in a hollow ash), atten- 

 uated downwards. The plant assumes partially a yellowish tint when dry or 

 cut. M.y.B. I have seen the plant growing in a hollow ash with the features 

 exactly as described by Berkeley. Spores 3x4 mk. W.G.S. Name— 5pvs, 

 oak. From its most frequent habitat. Pers. Syn. p. 478. Fr. Monogr. i. f. 

 237- Hym. Eur. p. 167. Berk. Eng. PL v. p. 70. Out. p. 134. C. Hbk. 

 71. no. Illust. PL 226. S. Mycol. Scot. n. 210. Hussey \\. t. 29,33. Vent. 

 t. 44. yC I, 2. A. dimidiatus Sch(sff. t. 233. 



361. A. spongiosus Fr.— Pileus 5-7.5 cent. (2-3 in.) broad, 

 tomentose with persistent cinereous down, fleshy, excentric, some- 

 what lateral, pulvinate ; flesh laxly floccose, white. Stem very 

 short, scarcely 2.5 cent, (i in.) long, or sometimes almost none, 

 incurved, not rooted, very excentric, white, tomentose. Ring 

 white, soon torn, appendiculate at the margin of the pileus, at 

 length quite vanishing. Gills sinuato-adnexed, with a decurrent 

 tooth, simple, separate, but crowded, quite entire, white. 



The flesh is soon pierced by insects like that of A. ostreatus. The gills 

 vary in breadth with the age of the plant. It seems to be widely removed 

 from A. dryinus, &c., in the substance being fleshy-spongy like that of ^. ostre- 

 atus, but still softer, as well as in the gills being sinuato-adnexed, but the veil is 

 quite the same. A very remarkable species. 



On rotten beech and mossy stumps. Rare. Oct.-Nov. 



The gills become beautifully yellow when old and dried. At a httle distance 

 it has exactly the appearance oi Polypo7'us betulifuts. Fries notes that it grows 

 among mosSjOn living beech trunks. Spores 11x4 mk. W.G.S. Name — 

 spongia, a sponge. From its texture. Fr. Monogr. i. p. 237. Hym. Eur. p. 

 167. B. b' Br. n. 1218. C. Hbk. n. in. Illust. PL 253. S. Mycol. Scot. 

 Supp. Scot. Nat. 1885. /. 21. 



■^* Veil none, gills sinuate or obtusely adnate. 



362. A. ulmarius Bull. — Pileus 7.5-12.5 cent. (3-5 in.) and more 

 broad, becoming pale-livid, often marbled with round spots, fleshy, 



