572 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
once in Muller’s fluid, wherein it remains for five months. The fluid is 
to be constantly renewed. A piece of the nerve is then cut off, and 
cleaned of superfluous connective tissue. After having been carefully 
washed in water, the piece is immersed in 1 per cent, corrosive sublimate 
for 24 hours. After removal from the sublimate, the piece is dried on 
blotting-paper and transferred to a 1 per cent, solution of sulphate of 
potash for at least 12 hours. The piece of nerve is then dried on 
blotting-paper and immersed in 0*5 per cent, osmic acid for 12 hours. 
Should the tissue be too dark, the excess of colour can be removed with 
permanganate of potash solution. Examinations of the specimens may 
be made from preparations teased out in glycerin, or from mounted 
celloidin sections cleared up with creosote. 
Specimens prepared by this method show striations parallel to the 
short axis of the cylinder, but not equidistant. In some, the appearances 
are serpentine, or rather like the worm of a corkscrew. From the 
appearances observed by this method of preparation, it would seem that 
the axis cylinders of nerves have a spiral course. 
Preparation of Nerve-Cells.* — Miss M. Lewis found that her best 
and clearest preparations of the nerve cells of a Polychaete were 
obtained from material prepared by one of vom Path’s osmic mixtures. 
This experience is not in accordance with that of v. Lenhossek and 
Dehler, and Miss Lewis therefore took pains to confirm her results by 
using the methods of the former, namely, the use of corrosive sublimate, 
followed by iron luematoxylin. The conditions obtained by this method 
furnished an excellent confirmation of the preparations made with the 
vom Path mixture, but were in no respect better. In the first method 
employed, the material was allowed to remain in the vom Path mixture 
(picric -f- osmic -f- acetic -+* platinic chloride) 8 days. It was then 
washed for a short time in methyl-alcohol, followed by pyroligneous acid 
for 48 hours. Then it was transferred to absolute alcohol, where it was 
allowed to remain for several days, with frequent changes of alcohol. 
Further staining was unnecessary. The sections were cut 3*3 fx thick, 
were mounted in Canada balsam, and gave most satisfactory results. 
Material prepared by the sublimate method sometimes showed shrinkage 
of the protoplasm. 
(3) Cutting-, including Imbedding and Microtomes. 
New Simple Microtome. — Herr G. Marpmann f describes a micro- 
tome the general aspect of which resembles the Cathcart. A clairtL to 
consideration is raised for the preparation clamp, which is stated to be 
“ very practical and apparently new.” This claim is founded on the use 
of the ball-and-socket joint. In neither of the illustrations is the novel 
arrangement clearly shown. The screw for raising the preparation has 
a thread rising 1 mm. 
New Fromme Microtomes.* — Prof. J. Schaffer describes the micro- 
tomes recently brought out by the firm of Fromme, of Vienna. 
I* Anat. Anzeig., xii. ("1836) pp. 292-3. 
+ Zeitschr. f. ang. Mikr , ii. (1896) pp. 65-8 (2 figs.). 
X Zeitsch. f. wiss. Mikr., xiii. (1896) jp. 1-9. 
