44 
FERNS AND FERNERIES. 
which it must be allowed to soak for three or four days, 
then transferred to a clean glass slip three by one inch, 
a drop of Canada balsam placed on it, and a small 
square or circle of microscopic thin glass placed over; 
give slight pressure with a wire clip until the balsam is 
dry, which will take a week or more. 
The other section, which is to be mounted in jelly 
(Deane’s glycerine jelly is the best), must be placed in 
water for a few hours, then transferred to pure glycerine, 
allowed to soak for a day or two, and then mounted in 
the jelly thus : With a penknife take from the bottle a 
piece about the size of a pea, place this in the centre of 
a glass slip three by one inch, warm the slide near a fire 
or over a small lamp until the jelly is dissolved, take 
the root section from the glycerine, drain off the glycerine 
and transfer to the jelly, cover with a circle of thin glass, 
and when quite set cover the edge of the thin glass with 
india-rubber cement. Both the upper and under cuticles 
of the frond ought also to be mounted. After cutting a 
small portion, half inch or less square, boil it in a test- 
tube with nitric acid and water in the proportion of one 
acid to six parts water. After a few minutes the cuticles 
