ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
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solution, 2 grin, of primulin are dissolved. The solution is filtered 
and allowed to cool. A cover-glass preparation is floated on the primulin 
solution in a watch-glass, the latter being placed in water at about 60°, 
and allowed to remain there for some hours, or indeed all night. The 
preparation is then washed with water, and stained with Hessian Bor- 
deaux for 1/2-2 minutes. The Bordeaux solutionis made by dissolving 
1 per cent, of, the pigment in boiling water and filtering once or twice. 
The preparation, after having been washed, is mounted. 
The cultures from which the preparations were made were from 
glycerin-agar media, the coli being 20-24 hours old and the typhoid 
about 13 hours. 
Examining the Nephrostomes of Selachia.* — M. F. Guitel de- 
scribes a simple procedure for showing the nephrostomes of the kidney 
of the adult Acanthias vulgaris. The body is opened along the ventral 
middle line, and Flemming’s fluid poured in. The solution, which is 
composed of chromic acid 1 per cent. 15 parts, osmic acid 2 per cent. 
4 parts, and glacial acetic acid 1 part, is allowed to act for a minute and a 
half. The fixative is then poured off, and the ventral cavity quickly and 
thoroughly washed with water. As the tissue of the nephrostomes fixes 
the osmic acid more strongly than the surrounding parts, these organs, 
stained black to chestnut brown, show up well against the dark grey of 
the adjacent tissues. The reaction attains its maximum in 24 hours. 
The pieces thus prepared keep well in alcohol or in 2 per thousand 
carbolic acid. 
Microscopical Examination of Viscous Urine.f — Herr G. Michel 
employs the following method in order to separate the organised deposit 
in albuminous viscous urines for microscopical examination. 50 ccm. of 
the urine are shaken several times with 20 ccm. of ether in a cylinder of 
100 ccm. capacity and the mixture set aside for some time. The ethereal 
layer will then contain all the organised elements. It is drawn off with 
a pipette into watch-glasses, and after evaporation of the ether, the 
residue is removed to slides for microscopical examination. 
Hew Method of Be calcifying.! — Dr. E. Rousseau has devised the 
following method for decalcifying. 
The objects to be decalcified, which should not be too large, are im- 
bedded in celloidin in the ordinary way, i.e. after fixation, are dehydrated 
in alcohol, and then, after having been immersed in a mixture of equal 
parts of ether and alcohol, are impregnated with celloidin in solutions 
of increasing strength (4 per cent., 8 per cent., 12 per cent.). When the 
objects are sufficiently saturated with celloidin, the latter is hardened by 
slow evaporation, by alcohol or by chloroform. The celloidin blocks 
containing the objects are next immersed in a mixture of alcohol at 90° 
and nitric acid, the proportion of the latter being regulated by the 
amount of calcareous matter to be got rid of. The author uses 10 to 50 
parts HN0 3 to 100 of alcohol. The decalcifying fluid should be re- 
newed from time to time, and when decalcification is complete, the excess 
of acid is removed by washing in water and immersion in 90 p. c. alcohol, 
* Arch. Zool. Exper. et Gen., v. (1897) pp. 385-8 (1 pi.). 
t Chem. Zeit., xxi. p. 316. See Pharmaceut. Journ., 1898, p. 324. 
X Bull. Soc. Beige de Microscopie, xxiii. (1896-97) pp. 159-65. 
