THE OVARY OF THE SPERMOPHILE a 
the state of nutrition of the uterus during the years of sexual 
activity.”” He thought it ruled over the phenomena of rut as 
well as pregnancy. 
About this same time Marshall and Jolly published a series of 
experiments very similar to Fraenkel’s. They used dogs and 
rabbits, and their conclusions were much like those of Fraenkel. 
Daels (08) published a paper in which he gives his several 
objections to Fraenkel’s theories and records a series of experi- 
ments on guinea-pigs. In his first series of experiments he tried 
to determine the influence of bilateral ovariectomy on the 
pregnant animal, concluding that this operation in the pregnant 
animal always interrupts pregnancy during more than the first 
half of its duration. He also tried giving Fraenkel’s lutein 
tablets, with no results.. He had better results from a product 
of the whole ovary. 
Ancel and Bouin (’08-’09) contributed several papers to the 
literature on the corpus luteum. They believed with Fraenkel 
that the corpus luteum produced rut and the other changes 
incident to pregnancy. They performed a series of experiments 
on rabbits in which they produced an unfertile coitus either 
between a normal female and a male in which a part of the vas 
deferens had been resected, and a female in which a part of the 
uterus had been resected and a normal male. They wished by 
these experiments to eliminate any action of the egg and the 
placenta on any changes taking place in the uterus incident to 
ovulation. They describe structural changes in the uterus and 
mammary glands for a period equal to the period of activity 
of the yellow body. 
In this same year (’09) two other Frenchmen, Regaud and 
Dubreuil, published several articles. ‘They were particularly in- 
terested in the cause of rut and ovulation. They made asystem- 
atic study of a large number of uteri and ovaries in different 
phases of the genital cycle and concluded that rut is independent 
of the corpora lutea, and that it is improbable that the corpora 
lutea plays a réle in originating the pregestative changes in the 
uterus, for the graphic curve of their development is much later 
chronologically than the curve of its changes. They claim that 
