Reproduction of Cyst op us Candidus, Ldv, 313 
superfluous moisture sucked up with blotting paper and the 
slide allowed to dry at the ordinary temperature of the room 
or in a gentle heat. There is no need to use any kind of 
cement if one is very careful to allow the drying to be com- 
plete. The paraffin is then melted and dissolved in xylol 
From xylol the slide is transferred to absolute alcohol and 
then to 90 c / o spirit, where it may remain until a convenient 
time for staining. 
The methods of staining adopted have been various, but 
the one which gives most beautiful and satisfactory results is 
a slight modification of one kindly communicated to me by 
Prof. Hartog and devised by him. The solutions used are 
those recommended by Hartog, somewhat modified for my 
purpose, viz. 
1. 50 °/ o spirit, 4 vols. ; glacial ac. ac. 1 vol. 
2. To solution 1 enough nigrosin is added to make it opaque 
in the bottle and transparent in a half-inch layer. 
3. To solution 1 enough nigrosin is added to make it blue, 
but transparent in a layer two inches thick. 
4. 5° °/ 0 spirit? to which a small quantity of 2 is added to 
make it quite light blue in colour. 
5. Mayer’s alcoholic solution of carmine. 
The sections are placed for about five to ten minutes in the 
mordanting solution 4. 
They are then placed in Mayer’s carmine for a few minutes 
until they become stained distinctly red, then washed in 30 °/ o 
spirit and placed in solution 3. If a deep stain is required 
solution 2 must be used. 
The sections remain in solution 3, called by Prof. Hartog 
a toning solution, until the required effect has been produced. 
The exact stage at which the operation should be stopped 
can be easily determined by observing the sections under the 
microscope. In order to produce a very clear and well- 
differentiated stain, I next transfer the sections to solution 1, 
in which a good part of the stain becomes washed out, leaving 
the nuclei beautifully differentiated and every part clearly 
shown up. It requires considerable practice to enable one 
