AGARICUS SUBRUFESCENS, Peck. 
The species of Agaricus illustrated on the opposite page has interested 
amateurs of mushrooms in the neighborhood of Boston in the last few 
years by its distinct and striking characteristics and its vigorous behav¬ 
ior. Its spontaneous appearance in various greenhouses in widely sepa¬ 
rate localities has brought it to notice at various times because it forced 
itself so persistently and abundantly on the owners that they have sent in 
specimens to the Club exhibitions in order to learn whether the visitation 
was to be regarded as a curse or as a blessing. Happily it has been pos¬ 
sible to tell them that Agaricus subrufescens was to be looked upon as a 
valuable mushroom, easy to grow and to sell. Some of its “hosts” have 
marketed it to their profit, some even planting it out with good results 
During the months of August and September it has been reported from 
several places about Boston growing out of doors on compost heaps of 
dried leaves, but never, so far as is known, has it been found in a strictly 
wild state. When it appears it comes with a rush, having previously, 
with its strong growing, strand like mycelium, taken possession of some 
rich portion of soil, and then sends its abundant fruits to the light, 
undaunted by any overlying difficulties. 
It mav be recognized by the following description of Prof. Peck 
(Report 46, p. 25) “Pileus rather thin and fragile, at first deeply hemi¬ 
spherical, then convex or broadly expanded, often wavy or irregular, 
silky fibrillose or minutely and obscurely squamulose, varying in color 
from whitish or grayish to dull reddish brown, flesh white, unchangeable ; 
lamellae close, free, at first white or yellowish-white, then pinkish, finally 
blackish-brown ; stem minutely flocculose below the annulus, hollow, 
white, somewhat thickened or bulbous at the base ; the annulus mem¬ 
branous, white, externally flocculose ; the mycelium white, forming slen¬ 
der branching rootlike strings; spores elliptical, brown, .00024 to .00028 
in. long, .00015 to .0002 broad. 
Pileus 2 to 4 in. broad; stem 2 to 6 in. long, 4 to 8 lines thick. 
Leaf mold. Glen Cove. October. W. Falconer. Also cultivated. 
In the form of the young pileus and in its color in the reddish tinted 
specimens, also in the white color of the young lamellae, this species 
makes an approach to A. campestris var. rufescens, but unlike that variety 
the wounded flesh does not become red. From typical A. campestris it 
differs in many respects—in the thin flesh, the color of the young lam¬ 
ellae, the character of the stem and its annulus and in its mycelium. It 
resembles more closely A. placomyces and A. sylvaticus, but from the 
former it may be separated by the shape of the pileus and the more 
obscure character of its scales and by its annulus, from the latter, by the 
color of the pileus and the young lamellae and also by the annulus, which 
is externally floccose-squamulose and also not distant as in that species.” 
It will be noted that its marked characteristics are the deeply hemi¬ 
spherical shape of the cap, the whitish color of the young gills, the hol¬ 
low nature of the stem, the flocculent lower surface of the veil, the strong- 
almond odor and taste. (See 48th Report of the New York State 
Museum, pp. 138 to 140.) 
