* 
1892.] Microscopy. 633 
of the medulla. . The fresh tissue obtained by splitting the bone is 
fixed in Flemming’s fluid, or still better, in a saturated solution of 
mercuric chloride in a 1% salt solution. After 2-3 hours the object 
is transferred to a mixture of the 1% salt solution and 90% alcohol, 
where it remains for 48 hours. It is then hardened in alcohol. The 
best results were obtained by staining the sections in hematoxylin 
or an aqueous solution of safranin and decolorizing with picric acid- 
alcohol. The amount of picric acid added to the alcohol is a matter 
of experiment. The proportions must be such that the protoplasm of 
the leucocytes remains uncolored when the nuclei of the red blood 
corpuscles are yellow. Miiller’s fluid fixes the red blood corpuscles 
better than sublimate. The sections are stained for a minute in a few 
c.c.’s of water to which have been added several drops of Ehrlich- 
Biondi’s solution, then passed through the grades of alcohol, cleared in 
clove oil and mounted. The eosinophilous granules of the leucocytes 
are red or rose ; the erythroblasts and blood corpuscles dark orange-red. 
Léwit’s Method.'—In the study of leucoblasts and erythroblasts 
Léwit employs the following method: Small pieces of bone medulla 
are fixed in a 1%-2% solution of platinum chloride in which they 
remain from 12-48 hours, then washed in running water for 24 hours, 
run through the grades of alcohol and imbedded in paraffine. The 
sections are stained for 2—4 minutes in an alcoholic solution of safranin, 
thoroughly washed in alcohol and treated with iodine-picric acid, 
which is prepared as follows: To a watch glass of 1% alcoholic solu- 
tion of picric acid a drop or two of officinal iodine tincture is added. 
The sections remain in this solution for 10-30 seconds, when they are 
washed in alcohol, cleared in clove oil and mounted. Connective tis- 
sue and leucoblasts are yellow, erythroblasts red. If the sections are 
left too long in the iodine-picric acid or the solution is too strong all 
the elements appear a brownish-red. A little experience will soon 
enable one to obtain the desired results. 
Demarbaiz’s Method,’—In studying the‘division and degeneration of 
the giant cells of the marrow employs the following method: The 
tissue is fixed for 24 hours in a mixture of 
To Uhromic soid... cists Sli Bitsecvein 14 parts. 
Glacial acetic acid 1 part. 
Distilled water 18 parts. 
1Arch. f. mikro. Anat., Bd. xxxviii, p. 533, 1891. 
*La Cellule T. v, p. 27, 1889; Zeit. f. wiss. Mikros., Bd. vii, p. 73. 1890. 
tt 
