ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
709 
of malachite-green in anilin oil. Very thin sections are decolorized in 
2-3 minutes ; thicker ones require a correspondingly longer time. The 
sections are then placed in turpentine for a short time (they should be 
of a delicate blue-green hue) and then in xylol to remove the turpentine, 
after this they are ready to be mounted in balsam. 
Staining of other bacteria by the malachite-green method is done as 
follows : — (1) Stain sections in phenol fuchsin for 5 minutes. (2) Wash 
in water and then just immerse in spirit. (3) Remove to pure anilin oil 
until quite cleared up. (4) Wash out the anilin oil in turpentine 
(about 1 minute). (5) Transfer to more or less strong malachite-green 
anilin oil for 10 minutes or longer, according to thickness of section. 
(6) Immerse the section in turpentine, xylol, balsam. 
It may be mentioned that when sections are placed in turpentine 
they become covered with precipitated pigment. This soon disappears, 
and if the sections be left in too long the malachite-green is completely 
extracted. It is, however, impossible to give an approximate notion of 
the time required for treating with turpentine. If, however, the green 
be too much extracted, the sections may of course be returned to the 
malachite-oil. 
The staining of the bacteria is said to be quite undisturbed by this 
treatment. 
Double and Metallic Stains .* — Prof. A. B. Aubert has prepared the 
following useful compilation. 
Bismarck Brown and Methyl- Green. — Bismarck brown, a concentrated 
warm aqueous solution, or a weak alcoholic solution. Methyl-green, 0*5; 
water, 100. Sections to be kept in about 15 minutes ; wash with water, 
stain dark green, wash, soaking in alcohol until grass-green ; clear in 
oil of bergamot, xylol ; mount in balsam. 
Borax-Carmine and Indigo-Carmine. — 1. Carmine, 2 grm. ; borax, 
8 grm. ; water, 130 grm. 2. Indigo-carmine, 8 grm. ; borax, 8 grm. ; 
water, 130 grm. Mix 1 vol. of 1 and 2. Sections are taken from 
alcohol and stained in from 15 to 20 minutes; transfer from 15 to 
20 minutes to concentrated solution of oxalic acid ; wash ; dehydrate ; 
mount in balsam. 
Eosin and Methyl-Green. — I. Eosin, 1 part ; methyl-green, 60 parts ; 
alcohol, 30 percent.; warm. II. A. Eosin, 1 part; water, 50; alcohol, 
50. B. Methyl-green, 1 ; water, 100. Sections stain in I. in 5 or 
10 minutes ; quickly wash in successive alcohols, mount in balsam or 
glycerin. II. is for blood-corpuscles; dry the blood (thin layer) on 
the slide ; treat with A 3 or 4 minutes, wash stain off with water ; treat 
with B 2 or 3 minutes, wash, dry, mount in balsam (red corpuscles red, 
nuclei and leucocytes bluish-green). 
Fuchsin and Methylin-Blue . — A. Fuchsin solution in alcohol, 8 to 
10 drops ; water, a watchglass-ful. B. Concentrated aqueous solution of 
methylin-blue. Tissues to be hardened in chromic acid, &c. ; stained 
in A for several to 24 hours ; washed with alcohol, stained in B for 4 to 
5 minutes (nuclei red, tissues blue). 
Hsematoxylin and Eosin . — Solution of eosin in glycerin in which 
some salt has been dissolved ; concentrated solution of alum in glycerin 
* The Microscope, xii. (1892) pp. 152 and 3. 
