Laboratory Aotes. 
GLYCERINE JELLY AND STAINING. 
i 29 
HEN making preparations which have to be mounted in 
EN making preparations which have to be mounted in 
Glycerine Jelly, it is often desirable to handle the sections 
as little as possible and not to prolong the process more than 
necessary. The following method is simple and effectual and 
contributes to this end. 
It consists of using the mounting medium coloured by means of 
some aniline dyes so that the sections may be mounted and stained 
at the same time. This medium is easily prepared by adding a few 
drops of an aqueous solution of the dye required to warm glycerine 
jelly, till it is moderately coloured. Sections of plants when 
mounted in this glycerine jelly will gradually become stained by a 
process of slow diffusion. 
Safranin used thus is very satisfactory ; if the jelly be only faintly, 
coloured, it clearly differentiates the lignified and cuticularized 
elements, but if the jelly is well coloured, the parenchyma is also 
stained. It is also adapted for sections of stems or leaves showing 
fungus tissues such as the Uredineae, etc., when the byphas will in 
many cases be coloured by the stain, as will also the young spores. 
Gentian-Violet and Hoffmann’s Blue are also useful when employed 
thus in connection with fungal byphas ; the former readily stains all 
the tissues and the latter more particularly the protoplasmic 
contents. 
In making glycerine preparations of Fungi generally, this 
method of mounting will be found satisfactory. Many Discomycetes, 
such as Peziza and Lachnea are readily stained thus and form clear 
and distinct preparations. But when dealing with Fungi the 
staining properties will be found to depend much on the Individual 
Fungus, indeed some forms refuse to be stained at all in this way. 
Coloured jelly may also be conveniently employed when 
mounting sections of Mosses or Hepatics, and Gentian-Violet or 
Safranin may be used as a general stain. It is also quite suitable 
for many of the Red and Brown Algye. 
This plan of staining will be found to save much time when a 
number of preparations are required ; and besides this advantage 
there is less risk of damage to the sections, than when the ordinary 
method is followed. 
Royal College of Science, 
December , 1901. 
A. D. Cotton. 
