54 THE NORTHERN MICROSCOPIST. 
mounted in this manner which seem to be keeping well, but of 
course it is absolutely necessary to get rid of all moisture before 
sealing up. 
The exceedingly dark and carbonized species are perhaps best 
put up in gum dammar dissolved in benzol, as the flocci can be 
seen to the best advantage when mounted in this manner. Those 
which can neither be mounted in dammar, nor yet dry, may 
be put up in glycerine jelly, glycerine, Deane’s medium, carbolized 
water, or a solution of salicylic acid; but whatever be the medium 
do not proceed to ringing or ornamenting the cover glass until 
after a fortnight from the time of mounting, when every slide should 
be examined under a moderate power, and all imperfect objects 
discarded and cleaned off. 
It is useless to keep slides of collapsed or burst threads or spores, 
“ee the sooner these abortions are expunged from our cabinets the 
etter. 
So much then for common moulds and mildews; observers are 
required even for these common productions, so that we may have 
their complete life histories Here is work for a thousand 
microscopes, let us hope that some of the unused instruments may 
find it in this direction. 
MOUNTING MARINE ALG. 
By Co ¥. Joxes, 
T a recent meeting of our Microscopical Society some mounted 
specimens of marine algze were shown, which though they 
were very well displayed had so far lost their colour as to be iden- 
tified with difficulty. 
Now I maintain that every object which is mounted for 
microscopical observation should show as many characteristics as 
is possible of the living plant, and the first thing one has to look 
to is the preservation of the colour. This, most mounters fail to 
do, for having mounted in balsam they have gone through the 
customary process of soaking in turpentine, and this has been the 
means of discharging the colour. 
For my own part, I prefer to mount a// marine alge in balsam; 
some prefer glycerine, Deane’s medium or glycerine jelly, while 
others extol the virtues of a fluid for this purpose. With many 
species of alge, glycerine jelly or Deane’s medium cannot be used 
so as to leave the specimen as it exists in nature, owing to an 
action on the endochrome, which often takes place in marine 
algee, exactly in the same manner as with fresh-water species. 
Dr. Carpenter, in his work on “The Microscope,” p. 351, shows 
