STUDIES IN THE EXPERIMENTAL ANALYSIS OF SEX. 451 
spermatozoa, in opposition to the earlier and very incomplete 
experiments of Mantegazza. 
Herlitzka, using Tritons, transplanted tlie testes from one 
animal into the abdominal cavity of another, and his experi- 
ments lasted two months. At the end of this time he states 
that in both males and females the alio- transplan ted testes 
were nearly completely replaced by fibrous tissue, which he 
believes to have been derived entirely from the host. He 
apparently did not make any auto-transplantations, so that 
though his results agree with our own, they do not throw any 
light upon the survival or destruction of the spermatogonia 
in the two cases. 
C. R. Stockard ( 11 ) has recently made some experiments 
in which he transplanted the ovaries of guinea-pigs and 
salamanders onto various organs, e.g. the testis and liver 
of the male. He states that the ovaries when transplanted 
on to the testes “ lived ” better than on the liver. After 
forty-one days he finds no degeneration either of* eggs or 
stroma or young follicles, but after seven months the ova 
cells can no longer be distinguished, the entire transplanted 
piece being now of the stroma type. From the figures given 
we can only conclude that there was a complete destruction 
of the germinal part of the allo-transplanted ovary and its 
replacement by connective-tissue stroma, a conclusion which 
Stockard himself does not seem to draw. 
We may give a short summary of other work upon the 
transplantation of gonads in other branches of the Verte- 
brata. 
Successful auto-transplantation of ovaries in the rabbit has 
been claimed by Knauer, Ribbert ( 4 ), Grigorieff, Rubinstein, 
and Halban, and all these authors claim that the presence of 
the auto-transplanted ovary stops the atrophy of the uterus. 
Hunter and Berthold and Foges (7), for the cock, state 
that pieces of testis can be successfully auto-transplanted, 
and that the presence of such grafts in an abnormal situation 
may permit the development of the male secondary sexual 
characters, although the testes have been otherwise removed. 
