COPRINUS STERQUILINUS 



167 



rise to mycelia (c/. Fig. 91, A and B). If now these one hundred 

 mycelia were all to develop equally well and independently of one 

 another, no single one of them would be large enough to give rise to 

 a fruit-body of even the 

 minimum size. All the my- 

 celia would remain sterile. 

 But what actually hap- 

 pens where one hundred 

 mycelia begin their de- 

 velopment simultaneously 



in the same dung-ball is 

 that, as already explained, 

 the mycelia become 

 united by hyphal fusions 

 into a three-dimensional 

 network of very fine mesh. 

 Competition thus becomes 

 converted into co-opera- 

 tion, with the result that 

 general sterility is replaced 

 by successful reproduction : 

 a single large fruit-body 

 is produced at the expense 

 of the whole compound 

 mycelium which is one hun- 

 dred times more extensive 

 than any of its components. 



The reproductively unsuccessful mycelia of the compound 

 mycehal network of Coprinus sterquilinus illustrated in Fig. 91, 

 D, are analogous to the neuters in a bee-hive that toil with all their 



Fig. 93 — co)it. 



more advanced stage of development. D : another leading radial hypha of a 

 mycelium like that shown at A, consisting of a series of cells each of which has 

 given rise to a fruit-body rudiment ; only one of these rudiments, namely, that 

 marked a, eventually developed into a perfect fruit-body, while all the others 

 became aborted. E : a fruit-body rudiment which has arisen on a secondary 

 branch of a mycelium and not on a leading radial hypha. Magnification : A, 

 11-25; BandE,395; CandD,225. The drawings copied by Dr. Nellie Carter 

 from Brefeld's Taf. I in Heft III of his Untersuchungen uber Pilze, and reproduced 

 on a slightly larger scale. 



Fig. 94. — Coprinus stercorarixis. To show the 

 origin of a fruit-body from a single cell of the 

 mycelium. A mycelial hypha (shaded) lies 

 in the background : one of its cells has given 

 rise to a fruit-body rudiment which is more 

 advanced in development than those shown 

 in Fig. 93. The rudiment has been flattened 

 otit in the culture mediimi by pressure on 

 the cover-glass so as to disclose its structure. 

 Its inner more compact part will develop into 

 the stipe and pileus, and its outer more 

 irregular hyphae into the volva. Magnifica- 

 tion, 338. The drawing copied by Dr. Nellie 

 Carter from Brefeld's Taf. II in Heft III of 

 his Untersuchungen uber Pilze, and repro- 

 duced on a slightly larger scale. 



