THE OVARY OF THE SPERMOPHILE 143 
have a special bearing on the function of the corpora rhe 
when they dea! with pregnant animals. 
Another much studied problem closely related to the {unction 
of the luteal bodies attempts to expla'n the means by wh ch 
ovulation s brought about and the results on the development 
of the corpora lutea i fertilization is prevented. 
Following are protocols and results of experiments performed 
in connection with these various problems. Only those experi- 
ments which proved operative successes and in which reliable 
data were obtained wil! be included. 
Series 1. Effects of the removal of the uterus on the ovaries of non- 
pregnant spermophiles 
Experiment 230-15 (spermophile 146). Captured in the spring of 
1915. Weight, 128 grams. Operated on June 11, 1915. Complete 
removal of the uterus. 
Gross observations. There are good-sized corpora lutea in the 
ovaries. 
Sacrificed July 20, 1915. 
Gross observations. The ovaries appeared very much smaller. 
Microscopic observations of the ovaries. Fixative, formalin zenker. 
Stain, hematoxylin and eosin. The ovaries show no degenerative 
changes except in the corpora lutea. These are undergoing regression. 
Connective tissue has heavily invaded every part of the luteal struc- 
ture. The blood-vessels are numerous and good sized. There are 
many fat vacuoles present. The decrease in size of these ovaries is 
no doubt due to the decrease in the size of the corpora lutea. 
Experiment 443-15 (spermophile 247). Captured in the spring of 
1915. Weight, 207 grams. Operated on October 1, 1915. Complete 
removal of the uterus. ' 
Died October 8, 1915. 
Gross observations. Death was due to peritonitis. 
Microscopic observations of the ovaries. Fixative, formalin zenker. 
Stain, hematoxylin and eosin. There is a marked congestion through- 
out the ovary. Many of the larger follicles are undergoing degenera- 
tion. Practically all the smaller follicles are markedly degenerated. 
This, no doubt, is a pathologie condition. 
Experiment 444-15 (spermophile 248). Captured in the spring of 
- 1915. Weight, 196 grams. Operated on October 1, 1915. 
Died January 13, 1916. 
Microscopic observations of the ovaries. Fixative, formalin zenker. 
Stain, hematoxylin and eosin. The great number of small hyalinized 
follicles are immediately apparent. They are so numerous that the 
THE AMERICAN JOURNAL OF ANATOMY, VOL. 25, No. 2 
