COPRINUS STERQUILINUS 



i8i 



very often a single fruit-body drains several dung-balls for its 

 substance. The presence of the superficial layer of persistent 

 mycelium and of the mycelial cords is evidently correlated with 

 the fact that the fungus produces large fruit-bodies from a sub- 

 stratum which is apt to be more or less divided into small portions. 

 To gather into a single vege- 

 tative body sufficient nutrient 

 matter to produce a sporo- 

 phore of average size for the 

 species, an apparatus has been 

 develojDed which unites the 

 mycelium present in several 

 dung -balls into a single system. 

 To make a culture of 

 Coprinus sterquiliniis free from 

 other fungi is a simple matter, 

 when once a fruit-body has 

 been obtained. My procedure 

 was usually as follows. About 

 twelve or fifteen fresh horse- 

 dung balls were placed in a 

 crystallising dish (7 inches 

 wide and 2-5 high), so that 

 they covered the bottom. The 

 dish, covered with a glass 

 plate, was then placed in a 

 steam steriliser and kejjt at 

 a temperature of 100° C. for forty-five minutes. It was then 

 removed from the steriliser and allowed to cool. Inoculation 

 was brought about by raising the cover of the dish and holding 

 a pileus, which was discharging spores, just above each dung-ball 

 for a few seconds. Various precautions were taken to prevent 

 the spores of other fungi from settling on the dung during this 

 operation. The spores invariably germinated and, after a few 

 days, the mycelium grew vigorously. From such a primary culture 

 as that just described new cultures were often made by transferring 

 pieces of the dung covered with the mycelium. Occasionally a 



Fig. 70. — Cojjriinifi fitcrquilinus. \ young 

 fruit-body leaving its annulus as a 

 volva attached to the stipe just above 

 the bulb. Natural size. 



