CULTURES OF COPRINUS COMATUS 173 



mycelium-covered dung was removed and used to inoculate the 

 sterilised dung in a second crystallising dish. Four such successive 

 transfers were made. The mycelium in each culture grew well and 

 covered the medium in 10-11 days. Moreover, its hyphae bore 

 large numbers of clamp-connections, thus showing that it was in the 

 secondary condition. Yet, although the cultures were kept moist 

 for several months, they never fruited. 



After these failures, I suggested to Miss Mounce that fruit-bodies 

 might develop in the laboratory if the culture medium, instead of 

 being exposed directly to the air, were buried beneath a thick layer 

 of soil ; for it was under such conditions, as already recorded, that 

 I had observed fruit-bodies appearing in the open. Accordingly, 

 Miss Mounce made two new soil-covered cultures in the following 

 manner. 



(1) A glass specimen jar, 11 inches high and 3 inches in diameter 

 (Fig. 67), was filled to a depth of 3 inches with a layer of horse dung 

 mixed with sawdust. This culture medium was packed down 

 solidly, and then the jar was filled to within an inch of the top with 

 sifted black soil. The whole was then covered with a glass plate 

 and sterilised in flowing steam for an hour on each of three successive 

 days. The inoculation was effected with mycelium from a stipe 

 culture. Two holes were made through the soil with a sterilised 

 glass rod, and through them small pieces of mycelium-covered dung 

 were pushed well down into the mixture of dung and sawdust in the 

 base of the jar. (2) A broad 3-litre beaker was filled to within 

 3 inches of the top with a mixture of dung and sawdust similar to 

 that used for the first culture ; and then the medium was covered 

 with a 2-inch layer of sifted black soil. The whole, after being 

 covered with a glass plate, was sterilised and inoculated in the 

 manner already described for the specimen- jar culture. The two 

 cultures, after inoculation, were set under large bell-jars on a table 

 near a window in the laboratory. ^ 



After inoculation the mycelium in the two glass vessels grew 



^ These and other particulars concerning Miss Mounce 's cultures are here given 

 partly from Miss Mounce's notes embodied in a paper called " The Production of 

 Fruit-bodies of Coprinus comatus in Laboratory Cultures," published in the Trans. 

 Brit. Myc. Soc, 1923, and partly from my own direct observations. 



