! 2 2 BASIDIOMYCE TES 



with about twenty species, of which some are regarded as edible *; 

 while among the black-spored types we have a single species of 

 Anellaria. 



It is, however, among the species with dark brown spores that 

 we have the largest number of annulate species ; these are mem- 

 bers of the genus Agaricus^ in its restricted sense which contains 

 among others the common field mushroom Agaricus campestris, 

 which is also the common mushroom of cultivation. There are 

 several allied species, almost any of which are edible. \ 



Agaricus canipestris is easily recognized by a combination of 

 characters all of which are to be found in the same individual. 

 Besides the veil which becomes an annulus, and free lamellae, the 

 plant must have pink lamellae when young changing to dark 

 brown or nearly black at the maturity of the spores, and a stuffed 

 stem, /'. e. , softer in the interior. A. Rodmani grows in similar 

 places, but has the lamellae white at first and narrower than the 

 thickness of the pileus, and a solid stem. A. aruensis and A. sub- 

 rufescens grow in similar localities, but have hollow stems ; the 

 former has an annulus formed of two layers the lower of which is 

 split into broad yellowish rays ; the latter has the annulus floccose 

 on its lower surface. A. hemorrhoidarius grows in woods and may 

 be recognized by its flesh changing to a dull red when wounded, 

 while A. placomyces and A. silvaticus growing in similar situa- 

 tions have white flesh ; the former has the pileus covered with 

 persistent brown scales, while the latter is without scales or has 

 only evanescent ones. A. maritimus, recently described, grows 

 along the coast of Massachusetts ; its flesh shows a pinkish or red- 

 dish color when cut or wounded and it has a short solid stem. 



Besides Agaricus with free lamellae, Stropharia has adnate la- 

 mellae, but while some species are common, scarcely any are of 

 economic importance. \ 



* Morgan (Jour. Cincinnati Soc. Nat. Hist. 6: 101-104) describes 

 eleven of these occurring in Ohio. 



| Hennings, loc at. , for some unexplained reason abandons the usual 

 practice of assigning the generic name Agaricus to this group and transfers 

 to a group of white-spored species. 



% Some thirteen species are found in America. Peck (Reg. Rep. 36: 

 41-49, and 48 : 133-143) describes the seven most common species. 



J Seven species are recorded from America. Morgan (Jour Cincin- 

 nati Soc. Nat. Hist. 6: 112, 113) describes three of these occurring in 



