CLASSIFICATION OV ACAKUS 695 



even. FLESH rather thin, firm, white al length tinged ashy. 

 GILLS adnexed, emarginate, rather broad, ventricose, close, white, 

 ;ii Length pale cinereous, edge minutely fimbriate. STEM '■'> <i cm. 

 long, 7 L5 imii. thick, equal or subequal, sometimes subbulbous or 

 tapering downward, short, stuffed then holloic, white or slightly 

 cinereous, innately silky fibrillose, shining, apes flocculose. 



SPORES broadly elliptical. 6-7 3 t-5 micr., si th, with a clear 



cavity on one side. CYSTIDIA none; sterile cells <>n edge of uills, 

 30-35x9 micr.. subclavate. ODOR cone. TASTE acrid, sometimes 

 Tardily so. 



Gregarious or subcaespitose. <>n the ground in frondose woods, 

 especially oak and maple Detroit. Aim Arbor, Jackson. Septem- 

 ber-November. Rather frequent. 



The acrid Tricholoma is probably the American form of T. muri- 

 naceum Bull., in the sense of Berkeley and Gillet, bu1 digers in the 

 closer gills and glabrous, not scaly, stem. The figures of Cooke (111., 

 Plate l!h ami Gillet. (Champignons de France, No. 683), are very 

 suggestive of our plant, except in the character of the 

 stem. T. murinaceum in the sense of Fries has a disagreeable, 

 strong odor, and was originally referred by him to Hygrophorus, 

 now //. nitratus Pr. Gillet's figure of T. portentosum is a fairly 

 good picture of some of our plants when the gills and stem are 

 white. T. acre is quite variable in size and in the shade of gray 

 of the cap. Normally the radiating fibrils <>f the pileus are pale 

 gray or silvery-gray, but in luxuriant individuals are much darker 

 gray or blackish, and in such examples the stem may be streaked 

 with dark fibrils. Sometimes the cap is almosl entirely white or 

 buff ami then silky or obscurely virgate, sometimes somewhal fiibril- 

 Lose-scaly <>n disk-. The plant is closely related to T. terreum, from 

 which it differs in its acrid taste, its firmer flesh, Larger size, pres- 

 ence of cystidia and flocculose, edge of gills and broader spores. 



