REPORT ON Kl'll'.ll M \(,I [895-99 [63 



purplish brown and finally to a cinnamon hue, which is due- to the color of 

 the spores by which they arc dusted. The stem is rather long and often 

 somewhat curved or flexuous. It is hollow in the mature plant. When 

 growing among mosses, it is often attenuated toward the base. The spe- 

 cies is rare with us. ] have found it in an extensive swamp only in Rens- 

 selaer count)-. 



Agaricus abruptus /'/. 



A.BRun Mushroom 



PI A I I 59, fig. ,\'-/J s 



Pileus ovate when young, becoming convex or nearly plane, rather thin 

 and fragile, smooth or slightly silky, shining, white, usually becoming tinged 

 with yellow in drying, flesh white ; lamellae narrow, close, thin, free, white 

 or whitish when very young, soon pinkish, finally brown or blackish brown ; 

 stem long, equal or slightly tapering upward, stuffed or hollow, terminating 

 below in an abrupt, flattened bulb, white, the annulus usually ample but 

 variable, flabby, entire or lacerated, tomentose and yellowish on the lower 

 surface, thin next the stem ; spores brown, elliptic, .00024 to .0003 of an inch 

 long, .00016 broad. 



The abrupt mushroom is very closely related to the forest mushroom, 

 A. sivic ol a, from which it ma)' be separated by the abrupt, flattened bulb 

 of the stem and the tomentose character of the collar. It is also liable to 

 be confused with the field mushroom, A. a rv en si s, but from this also it 

 may be distinguished by its peculiar bulb, by its thinner and more fragile 

 cap and by its place of growth. It is found in thin woods or along their 

 borders and occurs from July to September. It is either solitary, gregarious 

 or cespitose in its mode of growth. 



Its cap is generally quite regular and well formed though rather thin 

 and fragile. Its surface is smooth or slightly silk) - fibrillose, white when 

 fresh but apt to assume a yellowish hue in old or dried specimens. The 

 flesh is white. The gills are rather narrow and commonly a little broader 

 in the middle than at either end. They are free from the stem and are so 

 closely placed by the side of one another that they might almost be described 

 as crowded. In the very young or button state they are whitish, but on 

 exposure they soon become pink and finally assume the dark brown or black- 



