62 British Ftingi, 



• 

 tlie latter grow singly or concatenate, that is, in neck- 

 lace-like rows. Tliis cannot be done in water, as tlie 

 gonidia usually break away from each, other and from 

 the gonidiophore the instant they come in contact with, 

 water, but if placed in alcohol or good methylated 

 spirit no such separation of the gonidia takes place. 

 In examining microscopic fungi do not scrape off the 

 specimen, but cut a section. The latter process is a 

 trifle more difficult to accomplish, but results in some- 

 thing definite. For example, in examining one of the 

 numerous species of fungi parasitic on living leaves, if tbe 

 spores are scraped off they can certainly be seen, but 

 no idea of the structure of the fungus can be gained, 

 whereas if a section is cut through, tlie entire leaf at 

 tbe point wbere the fungus is situated, the attachment 

 of the spores is seen and also the mycelium in the 

 tissues of the leaf. Such, sections are not difficult to 

 obtain. If a small portion of the leaf containing a 

 IwMide, or cluster of spores, of the fungus is cut out 

 and placed on a piece of wood, then a glass slip or other 

 body with a straight-edge placed on the top of the 

 piece of leaf to serve as a guide for th.e razor or lancet, 

 and a section as thin as possible cut, a little experience 

 will skow that two or three sections can be cut with- 

 out moving tlie glass slip, and the pressure applied 

 will not injure the specimen. 



The razor should be dipped in water before cutting 

 the sections. Species growing on wood or bark 

 are generally sufficiently firm to admit of sec- 

 tions being cut without any pressure from above. 

 Satisfactory sections should be permanently mounted 

 for future reference, not omitting to indicate by a 



