THE OVARY OF THE SPERMOPHILE 147 
Experiment 61-16 (spermophile 381) Captured May 20, 1916. 
Weight, 145.5 grams. Operated on May 22, 1916. The uterus was 
removed to the cervix. 
Gross observations. The animal has given birth to young, probably 
a few days previously, as the uterus appears to be in an early stage of 
involution. There are good-sized corpora lutea in the ovaries. 
Sacrificed October 20, 1916. Weight, 170 grams. 
Gross observations. The ovaries are so small they are hard to find. 
Microscopic observations of the ovaries. Right ovary: fixative, 
formalin zenker; stain, hematoxylin and eosin. Left ovary; fixative, 
acetic osmic bichromate; stain, acid fuchsin and methyl green. There 
is nothing abnormal about the ovaries. They are very similar to other 
ovaries removed at this time. The corpora lutea have disappeared 
normally. 
Discussion and summary of results. Removal of the uterus 
has no apparent pathologic effect on the ovaries conta ning the 
corpora lutea of pregnancy. The latter pass through their 
norma’ cycle of development and regression. There seems to 
be a slight irregularity about the time at which the various 
changes in the life cycle come on; for instance, the corpora lutea 
in the ovaries of spermophile 348 seem to lose the red granules 
and take on the lipoid droplets sooner than normally. Then, in 
the ovaries of spermophile 349, the corpora lutea have retained 
their red granules longer than usual. However, this may not 
be significant since there is some irregularity about the cycle 
normally. 
Series 3. Effects of the removal of both ovaries on the uterus of 
non-pregnant animals 
Experiment 200-15 (spermophile 189). Captured in the spring of 
1915. Weight, 130 grams. Operated on May 28, 1915. Both ovaries 
were removed. 
Gross observations. The uterus is in a stage of early involution. 
Sacrificed April 22, 1916. 
Gross and microscopic observations of the uterus. Fixative, for- 
malin zenker. Stain, hematoxylin and eosin. The uterus is very 
small. It shows no signs of rut of having been in rut, either grossly 
or microscopically. This is very abnormal for this time of the year. 
A comparison of this uterus with a normal uterus in rut at this time of 
the year brings out the differences. (Compare figs. 1 and 3; also 
2and 4.) A comparison of the dimensions of the two uteri brings out 
the marked differences in size (table). 
