ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 
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be economized by leaving the preparation only two or three days therein, 
and then, while still saturated, placing them in a paper capsule, upon 
which may be written any necessary observations. Numbers of these 
capsules can then be placed in wide-mouthed bottles plugged with 
cotton wool soaked in spirit, previous to being corked. Only slices 
from the middle of large species should be preserved, but the whole 
specimen should bo previously hardened in 80 or 90 per cent, spirit. 
(3) Cutting-, including Imbedding and Microtomes. 
Method for Saturating Preparations with Paraffin.* — Instead of 
dehydrating tissues or pieces intended for paraffin imbedding, the fol- 
lowing method is recommended by Przewoski as being more economical, 
safer, and more easily applied than absolute alcohol : — After removal from 
ordinary spirit the preparation is immersed in auilin oil for 24 hours 
at least. It is then wiped, and the auilin oil removed by soaking in 
chloroform for 24 hours.. It is then immersed in paraffin dissolved 
in chloroform (40 per cent.), and the next day in melted paraffin, which 
must be cooled down as soon as possible, to prevent it becoming brittle. 
The anilin oil may be previously dehydrated by distillation or by 
dropping a piece of caustic potash therein. 
(4) Staining and Injecting. 
Demonstrating the Plasmodium Malariae.f — Herr E. Malachowski 
recommends the following method for staining the plasmodium malarias. 
Hardening in alcohol, floating the cover-glass in a mixture of eosin 
solution and dilute aqueous borax methylen-blue solution. The red 
discs are grey or yellowisli-red, the nuclei of white corpuscles red-violet, 
the plasma of the mononuclear leucocytes blue, that of the multinucleated 
pale violet, the plasmodia are blue, and certain granules within them, 
which have some relation to sporulation, red-violet. 
Herr J. Mannaberg f describes a new method for demonstrating the 
parasites of malaria. The preparation, dried in the air, is placed for 
12-24 hours in a mixture of equal parts of saturated picric acid solution 
and distilled water to which 3-5 per cent, acetic acid has been added. 
It is then quite decolorized in spirit, and having been over-stained with 
alum-hsematoxyliu solution, differentiated with 25 per cent, hydrochloric 
acid alcohol and dilute ammonia alcohol. By this method the red discs 
and the plasma of the white corpuscles remain unstained, the hsemato- 
blasts are faintly coloured, while the nuclei of the leucocytes and tho 
chromatin of the plasmodium are well stained. 
The author describes the young plasmodium as consisting of a thin 
layer of non-pigmented plasma, a large round nucleus situated excen- 
trically, and containing a nucleolus. In process of time the plasma 
differentiates into two layers, an ecto- and endoplasma ; and ultimately 
the plasmodium is distinguishable into its plasmatic and nuclear halves. 
* Centralbl. f. Allgem. Pathol, u. Pathol. Anat., 1890, No. 2G. See Bull. Soc. 
Beige de Microscopie, xliii. (1891) pp. 12-13. 
t Centralbl. f. Klin. Med., 1891, pp. 001-3. See Centralbl. f. Bakteriol. u. 
Parasitenk., x. (1891) p. 700. 
X Tom. cit., p. 513. See Centralbl. f. Bakteriol. u. Parasitenk., x. (1891) pp. 705-6. 
