ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
133 
matic microtomes by being small and compact, and does not cut in an 
arc like the Cambridge Rocking Microtome. 
The working parts are an oscillating lever, provided at one end with 
a clamp and at the other with a simple handle. This lever rests on 
trunnions supported in triangular notches at the top of the two pillars 
between which the lever oscillates. At the cutting end of the lever a 
spring pulls the lever down and effects the sectioning. The lever is 
adjusted for the successive sections by a hollow screw, through which 
passes the trunnion on the side away from the knife. This screw is 
fixed to a toothed wheel by the side of the lever. The toothed wheel 
and screw are actuated by a pawl fixed to the side of the lever near the 
handle. A fixed stop on the under side of the lever brings the lever to 
rest at a constant point in its downward course. An adjustable section 
throws the pawl ouc of gear after a given number of teeth have been 
turned through, so that it is possible to adjust the apparatus for cutting 
sections of any desired thickness. Sections can be cut from *0025 mm. 
to • 0625 mm. in thickness. 
(4) Staining: and Injecting". 
Subcutaneous Injections of Methylene-Blue.* — Herr S. Meyer has 
used this method for the demonstration of the elements of the central 
nervous system of Mammals. For the peripheral system, it is inferior 
to intravenous injection ; but Herr Meyer obtained, for instance, an 
extremely distinct staining of Purkinje’s cells in the cerebellar cortex. 
Success depends on two factors, the amount of stain which the animal 
will stand, and the length of time during which it can operate. Some 
of the results are striking, but the method seems cruel as the convulsions 
and agony tend to be prolonged. 
Alizarine. | — Dr. B. Rawitz recommends alizarin and alizarine 
cyanine for the differentiation of cell and nucleus. As neither are stains 
in the strict sense, the sections must be first treated with corrosive fluids 
(“ Beizflussigkeiten ”). The methods evidently require much care, and 
we must refer for details to the original paper. 
Modified Use of Haematein.l — Dr. B. Rawitz recommends the use of 
glycerin-alum-haematein solution in order to avoid over-staining with 
liEematein or haematoxylin. The receipt for the mixture is given in 
Rawitz’s ‘ Leitfaden fur histiologische Untersuchungen,’ 2nd edition. One 
to three drops of the concentrated solution are added to 25-50 ccm. of 
distilled water, and the objects are left there for 24-48 hours. Over- 
staining never occurs. 
Flagella Staining.§ — Dr. Pitfield recommends the following solution 
for staining flagella. The solution is made in two parts, which are 
filtered and mixed when required for use. 
(A) Saturated solution of alum, 10 ccm. ; saturated alcoholic solution 
of gentian violet, 1 ccm. 
(B) Tannic acid, 1 grm. ; I1 2 0, 10 ccm. 
Both solutions are to be made w r ith cold water. 
• 
* Arch. f. Mikr. Anat., xlvi. (1895) pp. 2S2-90 (1 pi.). 
t Anat. Anzeig., xi. (1895) pp. 294-300. J Tom. cit., pp. 301-3. 
§ Medical News, lxvii. (1895) p. 2G8, 
