COPRINUS STERQUILINUS 



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Fig. 90. — Coprinus sterquilinus, a homothallic Hymenomj'cete. Diagrams of a 

 vertical section through a horse-clung ball containing a single spore which 

 germinates and produces a mycelium that gives rise to a fruit-body. A, the 

 spore in the middle of the dung-ball. B, the spore has germinated ; the young 

 mycelium is at present in the haploid state, for as yet its nuclei (as shown by 

 special investigations) are isolated and non-conjugate, and it has not yet begun 

 to produce clamp-connexions ; also its branches have not yet begun to anasto- 

 mose with one another. C, the mycelium, now larger and older, has passed from 

 the haploid to the diploid phase, for its nuclei are now arranged in conjugate 

 pairs as indicated by the fact that it bears clamp-comiexions on all its leading 

 radial hyphae ; in the older part of the mycelium, lateral irregularly growing 

 hyphae are anastomosing with one another and with the radial hyphae, so that 

 the whole mycelium is becoming converted into a three-dimensional network. 

 D, the mycelium, now about a month old, has everywhere become converted 

 into a three-dimensional net-work and is exhausting itself by giving up its 

 contents to a single large fruit-body. The fruit-body is developing at the 

 expense of a single monosporous mycelium. The numerous hyphal fusions, 

 which here can have no sexual or social significance, make possible the con- 

 veyance of food-materials to the fruit-body through numerous channels. 



VOL. IV. 



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