234 MYCOLOGY 



fectly still air placed above a horizontal sheet of paper fall vertically 

 downward and produce a spore print of radiating lines of spores cor- 

 responding to the interlameUar spaces. The number of spores liberated 

 in Agaricus (JPsalliota) campestris (Fig. 94), 8 cm. in diameter, was 

 i,8oo,ooo,o<x) spores. Coprinus comatus formed 5,000,000,000 spores. 

 Such discharge under normal conditions is continuous, but by exposing 

 the giUs to ether, or chloroform vapor, it ceases. Buller determined 

 that the four spores on each basidiimi are discharged successively leav- 

 ing the sterigmata a few seconds or minutes of one another, so that an 

 entire mushroom will discharge in total about a million spores a minute 



Fig. 94. — Meadow mushroom. Agaricus campestris. A, View of under surface; 

 a, amiulus; g, gills; B, side view; s, stipe; p, pUeus or cap. (^From Gager, after W 4 

 MurriU.) 



for two or more days. The rate of fall of hymenomycetous spores ranges 

 from 0.3 to 6.0 mm. per second; those of the mushroom shortly after 

 they have left the gills fall at a speed approximately i mm. per second. 

 The path described by a spore in its fall has been called a sporabola. 

 Buller has divided the fruit bodies of the Agaricace^ into two types, 

 the Coprinus comatus type and the Agaricm campestris type. The 

 deliquescence in the first type is an autodigestion, which renders impor- 

 tant mechanic assistance in the process of spore discharge, where the 

 process proceeds in succession from below upward, so that autodiges- 

 tion removes those parts of the gills from which the spores have been 



