ipS Natural History Bulletin. 



rounded, and free behind, at first delicate pink, then brown to 

 almost black, becoming watery with age; stipe short, sHghtly 

 bulbous at base, stuffed, girt about the middle with a distinct 

 ragged ring. 



Spores rich brown in color, with a purplish tinge. 



Height 2 '-4'. Pileus about the same. Plate IV., Figs. 

 I and 2. 



This species will be easily recognized by the color of the 

 gills, or lamellae, at first -pink^ as the veil breaks aw^ay, becom- 

 ing brown, at length almost black. The pileus is rarely 

 smootli, usually silky, of various brown tints, sometimes 

 almost white. There are several varieties, but the variations 

 are chiefly in the surface of the pileus, and concern the color 

 and degree of silkiness. 



Not abundant, the edible mushroom may yet be found 

 common in richly manured gardens and fields, abandoned 

 stock-yards and similar places from August until October, or 

 later in favorable seasons. It is extensively cultivated in Iowa 

 and Illinois in green-houses, cellars, abandoned cement quarries 

 and caves, and it may be fairly questioned whether the species 

 has not been so introduced from the eastern states or from 

 England. 



A. arvensis, Schtef., is a native species closeh- related to the 

 " edible mushroom " and occurring in similar situations. It is 

 commonly called "horse mushroom," is a much coarser and 

 larger form, and, though edible, is not so highly esteemed as 

 is A. canipester. It may be usually distinguished by the 

 characters named, as well as by the fact that the lamellee are 

 at the outset white, then pink or flesh-color, at length brown. 

 The ring or annulus is much larger and more persistent. The 

 size is variable, but may be given: Height 3 '-4'- Pileus 3' 

 6'. Stipe often an inch or more thick. 



Both A. canipester and A. arvensis grow singly and in tufts. 



Our Puff-balls are nearlv all edible. Some, however, are 

 so small as to be of no practical value, and a few are not 

 palatable. The species we have selected to figure is one very 

 common in our region — 



