ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
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fixing liquid containing 90 parts of saturated solution of bichloride of 
mercury and 10 parts of glycerin. After staying in this for a quarter 
of an hour the animals may be treated with a series of alcohols, beginning 
with alcohol at 70° containing in solution a small quantity of camphor. 
Borax-carmine was found to be the best stain. 
Development of Cirripedia.* — Mr. T. T. Groom was able to trace 
in watch-glasses part of the development of ova of Cirripedes obtained 
by direct removal from the ovaries, but after a certain time the process 
invariably ceased ; the cause of this could not be discovered. Most of 
the embryos were sufficiently transparent to show most of the details 
of their anatomy by transmitted light ; Abbe’s condenser was frequently 
found to be of considerable assistance, the oblique light often being very 
necessary in order to make out the cell boundaries. 
For the histology of the embryos picro-nitric, picro-acetic, and picro- 
sulphuric acids and Perenyi’s fluid were good. For examination of 
unstained Nauplii weak osmic acid, as recommended by Dr. Koch, was 
found useful, as was also weak iodine. Embryos preserved with cor- 
rosive sublimate or with Perenyi’s fluid stained well with borax-carmine, 
but those that had been treated with chromic acid were difficult to stain, 
as might indeed be expected. 
A useful table is given of the months in which eggs, Nauplii or 
Cypris-stages have been obtained by the author or others. 
Preparing and Staining Cover-glass Preparations.-]- — Dr. A. A. 
Julien describes at some length procedures for obtaining undistorted 
and well stained preparations of micro-organisms and their cilia, and 
suggests that the dried bacterium film should be obtained in the fol- 
lowing way - A drop of the cultivation is to be diluted with sterilized 
distilled water. Some of this fluid is distributed on cover-glasses and 
the organisms there killed and fixed by the addition of some suitable 
reagent (e. g. tannin or chromic acid). The covers are allowed to dry 
slowly and at a low temperature. Before staining the film is treated 
with some mordant. The mordant recommended is a mixture of tannin 
and acetate of iron. (To 10 ccm. of 20 per cent, aqueous solution of 
tannin a solution of acetate of iron is added until it becomes violet-black ; 
then add 5-10 drops of acetic acid, and 4 ccm. of 12 per cent, carbolic 
acid, and filter.) For staining the films, a solution is made by mixing 
100 ccm. of anilin with 1 per cent, sodium hydrate added drop by drop 
until a neutral reaction is obtained. Then 1/2 grm. of fuchsin is dis- 
solved therein, with shaking. The solution must be filtered before using, 
and when it loses colour more fuchsin must be shaken up with it. 
The author lays considerable stress on two points, rapid fixation and 
slow drying of the film. 
C3) Cutting-, including Imbedding and Microtomes. 
New Double-knife. :j: — Herr P. SchiefFerdecker describes a new 
double knife made by W. Walb, of Heidelberg. As seen in fig. 33 the 
blades have the razor form. The handle, which like the blades is 
* Phil. Trans., 183 B. (1894) pp. 122-5. 
t Journ. New York Micr. Soc., x. (1894) pp. 1-14. 
X Zeitschr. f. wiss. Mikr., xi. (1894) pp. 4-5 (1 fig.). 
2 e 2 
