ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
277 
method, the author demonstrated that the ending was in the thick disc. 
A frog is curarized. The lymphatic sacs are injected to distension with 
2 per cent, bichromate of potash or ammonia. Eight or ten days after- 
wards, the retrolingual membrane is detached, and placed in water until it 
is decolorized. The epithelium is removed with a brush, and the 
preparation then stained with fresh hsematoxylin and alcoholic eosin. 
The membrane is then dehydrated in alcohol, cleared up in oil of cloves, 
and mounted in balsam. Thus prepared, the thick discs are stained a 
bright red, the thin discs present a yellowish-rose colour, while the 
clear spaces are absolutely uncoloured. 
In this way the succession of discs and clear spaces is easily followed 
right up into the tendon, where the muscle is seen to end as a rose- 
coloured hemispherical mass, which seems to correspond with a thick 
disc. 
Hence, the author concludes that muscle flbrillas end at the thick disc. 
Examining the histolytic phenomena occurring in the tail of Batra- 
chian Larvae.* — For paralysing batrachian larvae, Herr A. Looss prefers 
the use of an electric current (see this Journal, 1886, p. 700) to curara 
solutions, or to the pressure of a cover-glass. This method does not 
affect the histolytic processes which are taking place in the tail of the 
larva, and the only impediment to observation is the increasing pigmen- 
tation. The best fixative was found to be a mixture of sublimate and 
acetic acid (saturated aqueous solution of sublimate 150 ccm., distilled 
water 150 ccm., acetic acid 3-4 ccm.). After long washing in water, and 
having been tested with iodine alcohol to detect any remains of subli- 
mate, the preparations are carefully hardened. For this, Fol’s modification 
of Flemming’s chrom-osmium acetic acid is recommended, but Muller’s 
fluid, chromic acid, picric acid, and the mixture of chromic acid and 
platinum chloride are condemned. Staining was done in toto, in order 
to avoid damaging the preparation. Picrocarmine gave the best results, 
but acid -borax, alum and indigo-carmine, haematoxylin and anilin 
dyes were also employed. The paraffin imbedded sections (0*01 to 
0-0075 mm. thick) were stuck on with glycerin albumen, and finally 
mounted in balsam. 
For examining the so-called sarcolytes, decomposition- derivatives of 
striated muscle, Paneth’s method was used. This consists in overstaining 
with picrocarmine, and then, after extraction of the excess of pigment, 
with haematoxylin and then dehydrating. After the sections have been 
freed from paraffin and stuck on the slide, they are washed with undiluted 
alcohol (96 per cent, spirit and 2*5 to 3 per cent. HC1). This leaves 
the haematoxylin only in the nucleus, and after thoroughly washing with 
slightly ammoniacal spirit, in order to remove all trace of acid, the 
nuclei are seen clearly defined, of a pure blue colour, and lying in a more 
or less red mass of protoplasm. 
Examining the Blood for the Hsematozoon of Malaria.f — M. 
Laveran states that the best time for examining malarious blood is 
* Preissehr. d. Fiirstl. Jablonowski’schen Gesellschaft zu Leipzig . . . d. Matb.- 
Naturw. Section, 1889, 116 pp. and 4 pis. See Zeitsclir. f. Wiss. Mikr., vii. (1890) 
pp. 352-4. 
t La Semaine Med., x. (1890) No. 53. See Cenlralbl. f. Bakteriol. u. Parasitenk 
ix. (1890) pp. 15-6. 
