CHAPTER IV 



THE GERMINATION OF THE SPORES OF COPRINUS STER- 

 QUILINUS AND OF OTHER COPROPHILOUS COPRINI 



Coprinus sterquilinus and its Spores — In Nature, Spores of Coprinus sterquilinus 

 which Infect Horse Dung have all been previously Swallowed by Horses — 

 Presence of Bacteria Not Required for the Germination of the Spores of Coprinus 

 sterquilinus — High Temperature Not Required for Germination — Germination 

 of Spores immediately after their Discharge — Possible Effect of Bacteria on 

 Germination — The Struggle for the Substratum — Remarks on the Germination 

 of the Spores of other Coprini 



Coprinus sterquilinus and its Spores. — The production and liberation 

 of spores of Coprinus sterquilinus (Fig. 49) was treated of -in detail 

 in Vol. III. The fungus is coprophilous and can be found on horse 

 dung in pastures, gardens, and other places. As the pileus expands, 

 spore-discharge begins and, in the course of the few hours of the 

 spore-discharge period, the pileus sheds many millions of spores. 



A photomicrograph of some spores of Coprinus sterquilinus is 

 reproduced in Fig. 50. The spores fell on to and stuck to a dry 

 glass slide, and they were photographed undisturbed in situ in the 

 dry condition. It has been found far easier to obtain a good photo- 

 graph of C. sterquilinus spores when they are dry than when they 

 have been immersed in water under a cover-glass. 



Stages in the germination of some spores of Coprinus sterquilinus 

 are shown hi Fig. 51. The spores were taken from a spore-deposit 

 fourteen months old and were placed in cleared and sterilised 

 horse-dung agar, where they soon germinated. The mycelium 

 shown at F was produced from a spore which had been in the 

 culture medium only 17-5 hours. A germinating spore always 

 emits its germ-tube at its apex and from its germ-pore, and the 

 germ-tube soon begins to branch and to grow away from the spore 

 in all directions. In Fig. 51 the development of vacuoles is shown 



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