592 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
ous solution of formalin, 100 ccm.) ; (2) eosin-formalin (eosin 1 percent, 
in 60 per cent, alcoliol, 100 ccm. ; formalin 10 per cent, aqueous solution, 
20 ccm.) ; (3) metliylen-blue formalin (saturated aqueous solution of 
methylen-blue, formalin 4 per cent, aqueous solution). 
Blood preparations are first dried in the air, then stained for two 
minutes in solution 2, tlie excess of stain removed, and next stained for 
2 minutes with solution No. 3, after which they are washed in water 
and examined. For Gram’s method, gentian- violet-formalin was used, 
i.e. 10 ccm. of 10 per cent, alcoholic solution of gentian-violet, and 
100 ccm. of 2*5 per cent, aqueous solution of formalin. For staining 
gonococci the film need not be fixed in the flame, but merely treated at 
once with eosin-formalin for 2 minutes, and afterwards with a satu- 
rated aqueous solution of metliylen-blue. 
Double-Staining Vegetable Tissue.* — Herr H. Pfeiffer recommends 
a mixture of hsemalum and naplithylamin yellow for staining vegetable 
tissue, as it differentiates the lignified from the non-lignified tissue. The 
sections fixed in alcohol are placed in a mixture of equal parts of satu- 
rated aqueous solution of haemalum and naphthylamin yellow, for 30 to 
50 minutes. On removal they are washed in water for one or two 
minutes, placed on a slide, dehydrated, and mounted in the usual way. 
The ligneous tissue is stained yellow, the non-ligneous parenchymatous 
tissue violet. 
Triple Stain for Animal Tissues.! — Herr J. L. Graberg uses the 
following solution for staining sections of animal tissue : — 1 per cent, 
aqueous solution of Bordeaux red, 400 ccm. ; 0 • 5 per cent, aqueous solu- 
tion of thionin, 200 ccm. ; 1 per cent, aqueous solution of methyl-green 
with 25 per cent, alcohol, 300 ccm. The solution is filtered, and the 
sections immersed therein for 24 hours, after which they are thoroughly 
washed in 93 per cent, alcohol to which a few drops of acetic acid have 
been added, until they assume a reddish hue. The sections stain best 
when the material has been fixed in saturated solution of sublimate in 
0 • 7 per cent, salt solution. 
Method of Staining Nervous Tissue for Microscopic Purposes-! — 
Dr. Vastarini-Cresi stains the central nervous system for microscopic 
purposes by immersion in formalin (13 per thousand), for 2 weeks, the 
meninges being removed on the second or third day. Sections from 3-5 
cm. thick are placed in water, or better in 40 per cent, alcohol, for 12— 
24 hours, and then removed to 0*75 solution of silver nitrate, wherein 
they may remain for an indefinite period. The preparations are after- 
wards treated with water and 70 per cent, alcohol. Tissue thus prepared 
shows well the relations between the white and grey substances. 
C6) Miscellaneous. 
Demonstrating the Electric Organs of the Ray.§ — Herr E. Ballo- 
witz examined the electrical organs of the common ray, Raja clavata L., 
and found that not only the nerve-endings, but other structural elements 
* Zeitschr. f. wiss. Mikr., xiv. (1897) pp. 202-5. t Op. cit., xiii. (1896) pp. 460-1. 
X Rif. Meet., Feb. 14, 1896. See Brit. Med. Journ., 1896, i. Epit., 303. 
§ Zeitschr. f. wiss. Mikr., xiii. (1896) pp. 462-7. 
