460 PRACTICAL BOTANY 



duced from each basidium : note further the pale 

 colour of the tissue of the hymenium, and the rounded 

 ends of the paraphyses, and of those basidia which are 

 young, or have already produced mature spores. 



Attempts should be made to germinate the spores 

 in a decoction of horse- or cow-dung : a very small num- 

 ber of the spores should with a sterilized needle be 

 introduced into a drop of the decoction recently boiled, 

 the drop having been placed in the centre of a cover- 

 slip which had been recently heated. The cover-slip 

 is then to be inverted and placed over a moist chamber 

 constructed as described in Appendix A. The spores 

 can be examined at intervals under the microscope, and 

 the germination followed. 



A comparison may be made with Coprinus micaceus : this 

 Fungus appears almost with certainty if cow-dung be kept for 

 three or four weeks at a moderate temperature under a bell-glass : 

 if sections be cut from the lamellae, the structure of the hymenium 

 will appear similar to that above described, but the number of 

 sterigmata on each basidium is four. On species of Coprinus 

 large bladder-like cells (cystidia) are found projecting from the 

 hymenial layer. 



Examine specimens of other Hymen omycetous Fungi, e.g. 

 species of Polyporus, Dcedalea, Boletus, and Hydnum: note in 

 them the difference of conformation of the thallus, and especially 

 of the hymenial surface ; also the difference of texture : thus in 

 Dcedalea quercina, and in some species of Polyporus, the thallus 

 is hard, and of a corky or woody nature, while in others (e.g. 

 Polyporus giganteus) it is soft and succulent. 



Sections should be cut from the thallus of Dcedalea quercina, 

 or some other woody form : an examination of them will show 

 that, though the thallus is hard, the structure of it is similar to 

 that of the mushroom, the whole being composed of branched 

 septate hyphse. 



