The Royal Maternity Hospital

the rectum. In the aard-vark the testes occupy an intermediate position within the inguinal canal, but here there is reason to believe that they descend into the scrotum during the mating season. The testes of active creatures like ungulates, carnivores, and primates lie within a post-penile scrotum, where they are free from violent changes in pressure and are kept in the position of greatest safety.