Eeport of the State Botanist. 43 



its being mistaken for or confused with any deleterious or poisonous 

 species. 



The pileus is nearly always regular in shape, rather thick and mod- 

 erately firm, hemispherical or convex when young but usually becom- 

 ing more flattened or nearly plane with age. 



In its young state it is adorned with fine silky or hairy fibrils which 

 sometimes, with advancing age, form minute persistent tufts or scales 

 and sometimes disappear altogether, leaving the surface quite smooth. 

 The decurved margin usually extends a little beyond the extremity of 

 the lamellae. The cuticle or skin is more or less readily separable from 

 the flesh, which is white, but sometimes manifests a tendency to 

 change color slightly when cut or bruised, and to exhibit pinkish or 

 reddish stains. The color of the pileus in the wild form is usually 

 white or whitish with us, but in the cultivated forms it is often ochrey- 

 brown or pale tawny, and varieties sometimes occur in which it is 

 brown. 



The lamellae have a very beautiful and delicate pinkish hue which 

 is apparent as soon as they are exposed to the light by the separation 

 of the concealing veil from the margin of the pileus. This color grad- 

 ually becomes darker with advancing age until it finally changes to a 

 dark brown or almost black hue. This character is one of the best by 

 which to distinguish the "edible mushroom" from all other Agarics, 

 except its nearest allies, A. Rodmani and A. arvensis. And even from 

 these, when young, it may readily be distinguished by the primary 

 color of its lamellae. The subgenera Annularia and Pluteus in the 

 pink-spore series contain species the lamellae of which exhibit similar 

 pinkish colors, but these never change to brown or blackish-brown as 

 the plant matures or becomes old. In the mushroom the lamellae are 

 rounded at their inner extremity and not attached to the stem, so that 

 generally in mature specimens there is a small free space between it 

 and them. 



The stem is commonly short in proportion to the breadth of the 

 pileus, its length being, in most cases, less than the horizontal diame- 

 ter of the pileus. Ordinarily it is cylindrical in shape, though now 

 and then instances occur in which it may either be slightly thickened 

 or slightly narrowed toward the base. The central portion of the stem 

 is a little softer in texture than the external portion, hence it is said 

 to be stuffed. The annulus encircles it at or near the middle. It is 

 sometimes quite thin and flabby and is then easily torn and destroyed. 



The mushroom, like many other plants which have been the sub- 

 ject of long and extensive cultivation, has given rise to several forms 

 which exhibit quite marked distinctive features. These forms differ 



