io6 RESEARCHES ON FUNGI 



contact were practically obliterated. For the fourth and last 

 culture a smaller dish was found more suitable. In it were placed 

 only three dung-balls, and these were slightly separated from one 

 another so that they might be lighted all over their surfaces. All 

 the dishes were covered by glass plates and then sterilised in a 



Fig. 59. — Coprinus sterquilinus. Fruit -bodies which have arisen in cultures lighted 

 from above and darkened below. A, a horse-dung ball and the fruit-body 

 attached to it, removed from among other balls in the culture dish and photo- 

 graplied in lateral aspect. The fruit-body developed from a rudiment which 

 had its origin in the dark at the base of the dung- ball. B, another fruit-body, 

 photographed in situ in Culture A. It has arisen from a rudiment which came 

 into existence in a darkened crevice beneath and between two dung-balls. 

 It has a short, solid, somewhat bulbous stipe-base and a longer hollow stipe-shaft, 

 and the pileus is well advanced. Cf. Fig. 61 which shows fruit-bodies of the 

 same age grown entirely in the dark. Photographed 23 days after the culture 

 was started with mycelium. Natural size. 



steam steriHser by heating to 100° C. twice or thrice on successive 

 days, an hour each time. Inoculation was effected by holding a 

 pileus shedding spores over the dung for about half a minute or by 

 transferring pieces of mycelium from other pure cultures. 



Cultures A and B. Set up simultaneously. After inoculation, 

 the dish of A was covered at the bottom (outside) with black paper 

 and was then placed on a table at a window, so that it was lighted 

 by daylight from above and at the sides. The dish of B, on the 

 other hand, was covered with black paper above and at the sides, 



