LEAF FUNGI 107 



In the matter of naniiiig- the fuugi I shall be pleased 

 to be ol any assistance to intending collectors, and to le- 

 fer them to such descriptions of South African fungi 

 as have been jjublished up to date. 



Microscopic Preparations. 



A series of permanent microscopic preparations can 

 very easily be made, and serves a two-fold purpose; the 

 slides are handy for reference and comparison, and it is 

 not necessary to prepare a fresh slide every time a speci- 

 men is examined; in this way also the specimens suffer 

 less, as there is no need to destroy a part of the material 

 every time the fungus is studied under the microscope. 



]^xceptionally prett}' preparations can be made by the 

 method now to be described. Very little apparatus is re- 

 quired. Slides (3 by 1 inch), coverslips (No. 1, 2 by J in. 

 are the best), a small spirit lamp, one or two dissecting 

 knives, a glass rod, slide trays, and a few bottles for hold- 

 ing reagents are all that is necessary. 



There should be three (or four) fair-sized bottles, the 

 first containing pure xylol, another with a mixture of 

 alcohol and ether: — 



Alcohol (99%) 10 parts, 



Ether 32 parts, 



and the third containing a collodion mixture. 



The formula generally used for this is as follows: — 



Pyroxylin (soluble guncotton) .... 2 parts. 



Alcohol (99%) 10 parts. 



Ether 32 parts. 



Castor Oil .. 1 part. 



Lactic Acid 1 part. 



Failing this, the ordinary collodion obtainable from 

 any chemist can be used. A small bottle containing 

 Canada balsam dissolved in xylol will also be required, 

 and a small bottle of absolute alcohol will be useful. 



In the majority of cases perfectly satisfactory prepara- 

 tions can be made from dried leaves, but in the case of 



