. Discovery reports. Discovery (Ship); Scientific expeditions; Ocean; Antarctica; Falkland Islands. 442 DISCOVERY REPORTS in the Cetacea by the similarity between the male and the female ligamenta lata and the position of the testis. This " pseudo-hermaphroditism " reaches its maximum expression in the Mammalia among the Rodents, but among the Ungulates it is also found. The horse, donkey and zebra all have a Mullerian system developed as a long vagina mascu- lina like that of the Narwhal, bifid at its tip; while the goat and reindeer have long Mullerian ducts like those of Mesoplodo
. Discovery reports. Discovery (Ship); Scientific expeditions; Ocean; Antarctica; Falkland Islands. 442 DISCOVERY REPORTS in the Cetacea by the similarity between the male and the female ligamenta lata and the position of the testis. This " pseudo-hermaphroditism " reaches its maximum expression in the Mammalia among the Rodents, but among the Ungulates it is also found. The horse, donkey and zebra all have a Mullerian system developed as a long vagina mascu- lina like that of the Narwhal, bifid at its tip; while the goat and reindeer have long Mullerian ducts like those of Mesoplodon. (v) The absence of seminal vesicles. Since there is no convincing evidence that the small sacs described by various authors on the vasa deferentia really represent reduced seminal vesicles, it may be assumed that the vesiculae seminales are not merely secondarily absent from the Cetacean system. The absence of these organs may be assumed to be more primitive than their presence, especially as they are absent in the Monotremes. The Pinnipede Carnivores also lack seminal vesicles. The retraction of the penis into a penis sac by means of a pair of retractor penis muscles is perhaps the only specialized character observable in the male genital system of the Cetacea; it relates the system to that of the stallion in which a similar pair of re- tractor muscles is found and the penis becomes withdrawn into a sac in the inguinal region. After the above short comparative summary of the genital system of the Cetacea it will be seen that, besides many extremely primitive characters indicating not necessarily origin from, but affinity to some very primitive Insectivore-like mammal, the greatest number of points show resemblance to the Ungulata, especially the Perissodactyles. As pointed out by Anthony (1926) the Cetacea further resemble the Ungulata in having a non-deciduate diffuse placenta; while the Carnivora, which show many points of resemblance in their general anatomy to the Cetac
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