406 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
solution of powdered fuclisin dissolved to almost saturation in anilin w r ater 
and filtered. (6) Wash in distilled water. (7) Dry on blotting-paper 
and mount in balsam. 
By this method the author stained the flagella of Bac. cyanogenes , 
Proteus vulgaris and mirabilis , Bac. megaterium , mesentericus vulgatus. 
With the “ typhoid ” group the results were variable and inconstant ; 
thus, with Bac. typhosus the flagella sometimes stained and sometimes 
did not. Among the “typhoid-like” bacteria some varieties stained 
and others did not. The method failed with Bad. coli , and the Spirilla 
of Koch, Metschnikoff, Prior-Finkler and Deneke, though beautiful 
flagella were seen in some water-organisms. 
Staining Flagella.* — MM. M. Nicolle and V. Morax have simplified 
the somewhat complicated procedure invented by Loeffler for staining 
the flagella of vibrios. A small piece taken from a recent agar cultiva- 
tion is placed in a watchglassful of tap-water; the mixture should be 
only just cloudy. Some of this fluid is spread on clean cover-glasses 
which have been further purified by passing them frequently through the 
flame. The cover-glass held with forceps by the edge is inclined at an 
angle, and the superfluous fluid removed by means of a pipette. It 'is 
then allowed to dry without fixation in the flame. The surface is then 
covered with the mordant (aqueous solution of tannin 20 per cent., 10 
ccm. ; aqueous solution of cold saturated ferrous sulphate, 5 ccm. ; satu- 
rated alcoholic solution of fuchsin, 1 ccm.) and heated for 10 seconds. 
When the fluid begins to vaporize the mordant is tossed off and the surface 
washed by a stream of water from a dropper. The mordanting and washing 
are repeated three or four times more. After each washing the under 
surface of the cover-glass should be dried carefully. The preparation is 
next stained with phenol-fuchsin and heated once or twice for a quarter 
of a minute. It is then washed and examined in water. If the staining 
have been successful the cover-glass is dried and mounted in balsam. 
The points on which the authors lay most stress are that the cover- 
glasses should be perfectly clean, the mordant applied several times, and 
that the tannin must be pure. 
Staining Nuclei of Anthrax Spores.f — Dr. W. Ilkewicz has suc- 
ceeded in staining the nuclei of anthrax spores by a modification of Kolos- 
sow’s method, which consists in first treating the preparation with osmic 
acid and afterwards with tannin or pyrogallic acids. The details of the 
process are as follows: — The cover-glasses smeared with anthrax are 
first fixed in the flame and afterwards in the osmic acid mixture, heated 
until the fluid begins to vaporize. It is then washed and treated a second 
time in the same way and afterwards goes through a similar process in 
the reducing fluid. It is then dried and examined in glycerin or balsam. 
The fixative is composed of 7 ccm. of a 1/2 per cent, osmic acid 
solution and 3 ccm. of formic acid. Kolossow’s reducing fluid is made 
by dissolving 30 grm. tannin in 100 ccm. of distilled water and allowing 
this to stand in an open vessel for 24 hours. It is then filtered and 
the filtrate mixed with 30 grm. pyrogallic acid dissolved in 100 ccm. 
distilled water. The mixture is further diluted with 250 ccm. distilled 
* Ann. Inst. Pasteur, vii. (1893) pp. 554-61 (15 figs.). 
t Centralbl. f. Bakteriol. u. Parasitenk., xv. (1894) pp. 261-7 (1 fig.). 
