86 STAINING TECHNIQUE 
LOEFFLER’S Morpant 
Tannic acid, 20 per cent aqueous........... 10 c.e. 
Ferrous sulphate, saturated aqueous......... 5 ¢.¢. 
Basic fuchsin, saturated alcoholic........... 1 c.c. 
Mix and filter after a short time. 
LOEFFLER’s STAIN 
Basic fuchsin, saturated aleoholic........... 2.5 ee. 
Carbolic acid. 2.2... eee ce eee 20.0 c.c. 
Van Ermengen’s Flagella Stain. I. Van Ermengen’s Mordant. 
Osmic acid... 0. 2k eee ce ce eee 50 c.c. 
Tannic acid aqueous 10-25 per cent......... 100 
Four drops of glacial acetic acid should be added to the above. 
II. Seer Bath. A 0.25 to 0.5 per cent solution of silver nitrate 
in distilled water. 
III. Reducing Bath. 
Gallic acid... ok. ccc cece eee eens 5 ¢.¢. 
Tannin. 2.0... 0.0.0 cece cc eect e eee 3 C.C. 
Sodium acetate fused... .............00.., 10 e.c. 
Distilled water... 0.00000 00. 350 ¢.¢. 
The smear should be covered with the mordant for fifteen minutes 
at 50° C. The mordant is then washed off in distilled water and 
alcohol. The smear is then placed in a small amount of the silver 
bath and gently heated. Without washing, it is then put into the 
reducing bath and agitated until the solution begins to blacken. It 
is removed dried and mounted for examination. The apparatus used 
in this procedure must be absolutely free from animal grease. Kuntze 
(1902) has suggested some improvements in Van Ermengen’s procedure 
for staining flagella, 
Acip Fast Stratnina 
This involves the formation of a permanent compound between the 
stain and the cell protoplasm—one which may not be removed by 
comparatively strong solutions of mineral acids. These bacteria 
