ei 
THE MICROSCOPE. 141 
THE ALCOHOLIC METHOD OF MOUNTING BRYOZOA 
POLYZOA—NOTES ON TECHNOLOGY. 
Vv. A. LATHAM, B. SC. F. R. M. 8. 
HAVE been trying to avoid the alcoholic method of mounting as 
it is difficult to render the slides permanent, especially as 
regards the cement. If it is wished to preserve them in alcohol I 
use brown cement; but not by itself, as the spirit affects it. Ring a 
cell of the brown cement and allow it to harden thoroughly; cover 
this entirely with balsam and benzole, and, when dry again, make it 
slightly sticky by a thin line of balsam, which fastens down the 
cover glass. Ring over all another layer of the last cement, and, 
when dry, use brown cement to completely seal the mount, which, 
when dry, can be finished as the mounter wishes. If, instead of the 
above method, after the organisms have been fixed and colored, pass 
them through alcohol 30 per cent., 50 per cent., 70 per cent., and 
absolute the last, at least twice, and let it stand covered for 24 hours. 
Replace the spirit by pure benzole; remove about a tenth of the 
alcohol in which the organisms are placed with a pipette, and replace 
by the same amount of benzole; repeat this a number of times (about 
12) at intervals of from ten to thirty minutes. Great care must be 
taken that the benzole mixes thoroughly; after the last addition 
pour it off and substitute pure benzole. At the end of 24 to 48 
hours in the benzole, which depends upon the size of the object, a 
fifth part of C. balsam dissolved in benzole is added; repeat this at 
intervals of from a quarter to half an hour; the objects may now be 
preserved in the tubes till wanted, or mounted at once. In mount- 
ing care must be taken that each drop holds in suspension a suffi- 
cient variety of the organisms. The method is not quite so tedious 
as it appears from the reading. 
Srarnine, CANCER OF THE Breast.—I find ink to be a useful, 
handy stain; also in secondary cancer, sections from Fallopian 
tubes, etc., especially if Steven’s blue-black ink is used, which is 
better than the black. 
Stwwes or Bioop.—Heat a slide, allow a drop of blood to fall 
upon it, and immediately (but lightly) wipe off; in this manner a 
sufficient quantity is dried on before the corpuscles have time to 
form in rouleaux or change shape. It is a good method of mounting 
blood from different animals, etc., for comparison. 
Srarnrnc SMa Investing to SHow Peyer’s Parcues.—Stain in 
picro-carmine; wash lightly in water acidulated with acetic acid; 
