ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
115 
tissues of the Hirudinea is also given by the author. The object is 
placed for half an hour in a half per cent, watery solution of haematoxylin, 
then having been quickly washed in distilled water, it is transferred 
for two hours to a 1 per cent, aqueous solution of bichromate of potash. 
It is then again washed and imbedded in celloidin. The sections, which 
should show a pale yellowish staining, are after ^stained in a weak 
aqueous alum-haematoxylin solution. 
New Method of Haematoxylin Staining."^— Dr. N. Kultschitzky 
advocates the following procedure as being more simple than Weigert’s 
method for staining nervous tissue. Pieces of brain or cord are hardened 
in Miiller’s or Erlitzki’s fluid, and imbedded in celloidin. The sections 
are then placed in the following haematoxylin solution : — 1 grm. of 
haematoxylin dissolved in a little alcohol is added to a mixture of 20 ccm. 
saturated watery solution of boracic acid and 20 ccm. distilled water. 
Before using this solution a little acetic acid is added (two or three 
drops to a watch-glassful). The sections require some few hours (to 24) 
for staining. The medullated nerve-fibres are stained blue, the rest of 
the tissue yellow, or yellowish-red. If the sections are then placed for 
twenty-four hours in a saturated watery solution of carbonate of soda or 
lithium the nerve-fibres become dark blue, while all the rest is almost 
uncoloured. Then alcohol, mount in balsam. 
A still more simple hfematoxylin solution, which gives the same 
results, is 100 ccm. of 2 per cent acetic acid, and 1 grm. of haematoxylin 
dissolved in a little alcohol. 
Simplification of Weigert’s Method. | — Dr. U. Eossi, who says that 
Weigert’s method is unnecessarily complicated, recommends the following 
simplified procedure : — Pieces of spinal cord or brain are fixed at the 
ordinary temperature, or in a thermostat at 35°, in the following solution : 
— distilled water 100 ccm., chromic acid 0*75-1 gramme, acetate of 
copper 5 grammes. The time required for hardening the human cord 
is six to eight days ; cord of dog, three to four days ; for the entire brain 
of the dog fifteen to eighteen days, and so on according to the size of 
the pieces. In the thermostat the fixing process is completed in half 
the time required for doing the same thing at the ordinary temperature. 
The pieces are next transferred to rectified spirit 24 to 48 hours, and 
afterwards to absolute alcohol. When properly hardened they are im- 
bedded in celloidin and sectioned. The sections are placed for staining 
in a vessel containing about 30 ccm. of rectified spirit, to which has 
been added 7 or 8 drops of a haematoxylin solution made as follows : 
absolute alcohol 20 ccm., haematoxylin 1 gramme. In less than 2 or 3 
hours the sections become dark, and they are then placed in some of the 
following solution : — absolute alcohol 100 ccm., hydrochloric acid 8 drops. 
Herein they assume a brick-red hue, and when tlie grey and white 
matters become differentiated they are removed to distilled water, wherein 
they quickly become blue. After this they are to be well washed again 
to remove all traces of acid, then dehydrated, cleared up, and mounted 
in balsam. 
In addition to the foregoing stain, the author says a double stain 
* Anat. Anzeig., iv. (1889) pp. 223-4. 
t Zeitschr. f. Wiss. Mikr., vi. (1889) pp. 182-4. 
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