6 
SPERMATOGENESIS OF NORMAL 
Graff’s chrom-oxalic mixture was found valuable for both 
chromatic and achromatic cellular structures. It was partic¬ 
ularly serviceable in the study of the interstitial and wandering 
cells. The forrnula which yielded the best results is the fol¬ 
lowing : 
Oxalic acid 8% = 4 vol. 
Alcohol 95% =3 vol. 
Chromic acid 1% =3 vol. 
Tissues were left in this fluid from 2 to 4 hours, and then 
washed in 35% alcohol. 
Corrosive sublimate preparations, although badly distorted 
in many cases, were serviceable for comparison when followed 
by the Biondi-Ehrlich triple stain or by cyanin and erythrosin. 
The same may be said for picro-formalin-acetic preparations. 
The latter were invaluable in studying the centrosome, partic¬ 
ularly during its transformation to form the axial fiber of the 
tail. Corrosive sublimate was substituted for the picric acid in 
some cases in the last named fluid, with the result that the stain¬ 
ing of the axial filament was more precise. 
Besides the above methods, maceration was also employed 
and was of very great service in giving a general idea of the 
structure of the entire cell, the connection of the spermatozoa 
with the supporting cells, and the structure and transformation 
of spermatozoa. The most satisfactory results were obtained 
from Hertwig’s well known macerating fluid. Various stains 
were employed after such treatment, prominent among which 
were acid carmine and methyl green. 
In studying the transformation of the spermatid to the sper¬ 
matozoon in sections, the best results were obtained from 
material fixed in corrosive sublimate and stained in Delafield’s 
haematoxylin, with an after treatment of acid fuchsin and picric 
acid. Both thick and thin sections were necessary. Gilson 
material, followed by the iron-haematoxylin method, and coun¬ 
ter-stained with Bordeaux red, was also good. 
Whole mounts of fresh spermatozoa were fairly distinct 
when treated with methyl green. Air dried specimens also 
stained readily with Schneider’s carmine or Delafield’s haema¬ 
toxylin. Perhaps the most valuable method for fixing the adult 
spermatozoa is to treat them for a few minutes on the slide with 
