Archive image from page 402 of Discovery reports (1932) Discovery reports discoveryreports05inst Year: 1932 MALE GENITAL SYSTEM: INTERNAL ORGANS 387 Discussion of the position of the testis Before closing the description of the testis and its ducts a little further attention must be given to the abdominal position of the testis in the Cetacea—a condition commonly known as 'testicondy'. All authors—notably Weber, Anthony and Meek—have insisted that the testicondy of the Cetacea is secondary and that descent took place in the Cetacean ancestor. Weber (1904), in his review of the question of th
Archive image from page 402 of Discovery reports (1932) Discovery reports discoveryreports05inst Year: 1932 MALE GENITAL SYSTEM: INTERNAL ORGANS 387 Discussion of the position of the testis Before closing the description of the testis and its ducts a little further attention must be given to the abdominal position of the testis in the Cetacea—a condition commonly known as 'testicondy'. All authors—notably Weber, Anthony and Meek—have insisted that the testicondy of the Cetacea is secondary and that descent took place in the Cetacean ancestor. Weber (1904), in his review of the question of the position of the testis among Mammalia generally, distinguished two kinds of testicondy. (i) True testicondy. No inguinal canal exists and the ligamentum inguinale is lacking. The testis retains its primitive dorsal position in the neighbourhood of the kidney, slung by the 'urinary ligament' which is a reduplication of the peritoneum and carries the early mesonephros (epididymis) and the vasa deferentia. This forms the plica diaphragmatica laterally. Such testicondy occurs in Monotremes, some Insecti- vores, the elephant and Hyrax. In some Edentates (Bradypodidae and Myrmecopha- gidae) the testes are pushed tailwards and lie be- tween the bladder and the rectum. They are likewise suspended in a urinary ligament. (ii) False testicondy. Here the ancestral descent has been secondarily abandoned and the testes lie in the abdominal cavity but have lost their former dorsal position and now lie ventrally. The inguinal canal is reduced in varying degrees and only indicated at most. This condition is seen best expressed in the Dasypodidae, where the testes lie against the ventral body wall. Except in Chlamydo- phorus, a wide inguinal ring exists, through which projects a small cremaster sac. Weber assigns the Cetacea to this class. The arguments in favour of placing the Cetacea among the secondarily testicondal animals are based chiefly upon the ventral position of the testis and
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