ZOOLOGY AND BOTANY, MICROSCOPY^ ETC. 
245 
Staining’ Blood of Oviparous Vertebrata.* — Dr. E. Giglio-Tos re- 
commends the following method for staining blood-films. The film 
should be dried quickly in the flame and immediately stained. The 
stain recommended is a saturated aqueous solution of methylen-blue B.X. 
One or two drops are placed on the film and left there for one minute. 
The preparation is then washed with distilled water, afterwards covered 
with a cover-glass, and luted with olive oil. In this way the preparation 
will keep for four or five days, and the results for observation are excel- 
lent. Attempts to make permanent preparations by means of glycerin 
and resin were failures. 
Permanent Stain for Starch.f— Prof. G. Lagerheim describes the 
following method for imparting a permanent brown stain to starch-grains. 
The material is first fixed with alcohol, and should it contain chlorophyll, 
must be left in the spirit until colourless. Eau de Javelle may be advan- 
tageously substituted for alcohol, as that fluid rapidly destroys the proto- 
plasm of the cells, leaving the starch-grains intact. The specimen, 
having been washed, is placed still wet on a slide, and then treated with 
an iodine solution of the following composition, — water 15 grm., potas- 
sium iodide 1*5 grm., iodine 0*5 grm. One drop or so of this solution 
usually suffices to stain the starch-grains blue. The preparation is next 
washed with distilled water until the cell-membranes and the plasma have 
lost their iodine staining, and is thereupon treated with one or more drops 
of a solution of nitrate of silver (? strength). The silver iodide precipi- 
tated in the starch-grains is now reduced by a developer of the following 
composition, — distilled water 100 grm., sodium sulphite 10 grm., hydro- 
chinon 2 grm. To one cubic centimetre of the developer is added a 
drop of 10 per cent, solution of potassium carbonate ; and the prepara- 
tion is treated with a few drops of this freshly made solution immediately 
after it has been washed with distilled water. The preparation now 
gradually becomes brown, and is mounted in glycerin. 
A brown staining of the starch-grains is also obtainable by treating 
the preparations, after the iodo-potassic iodide solution, with 1 per cent, 
solution of palladium chloride for a few minutes, and then carefully 
washing with water. 
Injection Mass.J — Herr O. Frankl uses a mass for injecting the 
kidney of frogs which was prepared of the following ingredients and in 
the following manner. Ten to fifteen plates of white gelatin were soaked 
in water for 24 hours ; the superfluous fluid was then poured off, and the 
mass boiled with an equal bulk of glycerin, and then, after the addition 
of 4-5 ccm. of sublimate water (coned.), was filtered. The mass, stained 
with 1-20 Berlin blue or 1—20 carmin, is injected warm. It keeps well 
if a thymol crystal be added. 
(5) Mounting, including Slides, Preservative Fluids, &c. 
Method of Preserving Algae. § — Mr. C. Thorn recommends the 
following method of preserving algae for demonstration purposes without 
shrinking. Fix in Flemming’s weaker formula ( 10 ccm. 1 per cent, osmic 
* Zeitschr. f. wiss. Mikr., xiv. (1897) pp. 359-65. f Tom. cit., pp. 350-2. 
+ Zeitschr. f. wiss. Zoologie, 1897, p. 63. See Zeitschr. f. angew. Mikr., iii. (1897) 
p. 265. § Bot. Gazette, xxiv. (1897) p. 373. 
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