746 



ADDITIONAL EXERCISES 



Cap 1 3^ to 4 inches broad; stem 2 to 3 inches long, 4 to 8 lines thick. (Fig. 266.) 

 This is the most common and best known of all the edible mushrooms. It is a 

 species of high commercial value, lending itself to very successful and profitable 

 artificial cultivation. It is cosmopolitan in its geographic distribution, being as 

 universally known abroad as in America. It is cultivated in caves, cellars, and in 

 especially constructed houses; but it also occurs abundantly in the wild state, appear- 

 ing in pastures, grassy places, and richly manured ground. The only danger in 

 collecting it in the wild form is in mistaking an Amanita for an Agaricus; however, 

 this danger may be obviated by waiting until the gills are decidedly pink before col- 

 lecting the mushrooms. 



Fig. 266. — Meadow mushroom, Agaricus campestris var. Columbia, showing all 

 stages in development of young mushrooms (fruit bodies). {From Gager, after G. F. 

 Atkinson.) 



Agaricus placomyces. Flat-cap Mushroom {Edible) 



Cap thin, at first broadly ovate, convex or expanded and flat in age, whitish, 

 adorned with numerous minute, brown scales, which become crowded in the center, 

 forming a large brown patch; gills close, white, then pinkish, finally blackish-brown; 

 veil broad; ring large. In the early stages, according to Prof. Atkinson, a portion of 

 the veil frequently encircles the stipe like a tube, while a part remains still stretched 

 over the gills. 



