44 
ON PRESERVING FUNGI 
One part sandarac, 2 parts mastic, and 2 parts Canada 
balsam, dissolved in 30 parts of 95 per cent, alcohol. In 
the use of this it has been found that the time of soaking 
necessary to fix the spores is for Boleti two minutes ; 
Dermini (= Ochrosporae) Coprinarii, Gomphidius, Paxillus, 
Russula, and Lactarius four to five minutes ; pink-spored 
agarics, also dark-brown-spored (as the meadow mushroom), 
and Cortinarii, six to eight minutes. It is important that 
the alcohol should be full strength. 
A gelatine solution is useful for white-spored species. 
This is prepared and used warm. Its strength varies with 
the species. 
Lepiota procera , Collybia radicata, and Clitocybe laccata may 
be fixed by a solution of 1 part gelatine to 30 parts of water. 
For species of Tricholoma this is too strong, and 1 to 60 or 1 
to 200 must be the formula. The difficulty arises here from 
the fact that an excess of gelatine makes the spores trans¬ 
parent, and even invisible. Their opacity may be secured 
by previous treatment with a solution of 1 part mastic in 30 
parts of ether. 
For certain kinds (Tricholoma personatum, Lepiota granulosa, 
Amanitopsis vaginata , and others which experiment will dis¬ 
cover), 10 to 25 per cent, of alcohol must be added to the 
gelatine solution in order to make the spores adhere. 
Experience will doubtless show that other fixatives may 
be used. Gum-arabic, for instance, suggests itself. This, 
however, if strong, is apt to cake the spores together. If 
one method fails, invention and repeated trials must find a 
successful means. 
