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Show 244 MR. G. E. DOBSON ON SECONDARY SEXUAL [Mar. 4, male Sea-elephant (Macrorhinus piroboscideus) and the Bladder-nosed Seal (Cystophora cristata) ; and Mr. Darwin, when referring to the sexual peculiarities of these animals, does not sugerest any use for the remarkable structures possessed by the males ; but cites Lesson, who " compares the erection of the proboscis [in M. pro-boscideus~\ to tbe swelling of the wattles of male gallinaceous birds whilst they court the females"*. I am disposed, however, to regard the protrusible frontal sac of the male Phyllorhine Bats as a more specialized structure than the erectile nose of M. proboscideus, or the inflatable skull-cap of C. cristatus. The peculiar finger-like appearance of the everted sac, armed at the extremity with a pencil of long straight hairs, seems to indicate that it acts as a delicate organ of touch, and is probably used by the male for exciting the female ; supplementing, in this respect, the very imperfect eye-sight f of these animals, as the highly sensitive wing-membrane and expanded foliaceous nasal appendages supplement the same in their search for food, enabling them also to avoid obstacles even in the darkest caverns and when totally deprived of the little sight they possess. In the genera Megaderma and Rhinolophus the females only possess peculiar pubic warts, resembling teats, which have been described by Temminck and other zoologists. Temminck regards them as odoriferous glands, in no manner connected with the function of nutrition, and writes : - " J'ai soumis un grand nombre d'individus de plusieurs especes differentes a l'examen de ces parties, et le resultat m'a pleinement convaincu que ces mamelons ne servent en aucune maniere a la nutrition, ce sont des appendices d'ou suinte une matiere onctueuse, fetide; cet appareil doit servir a augmenter 1'odeur desagreable que ces animaux exhalent, et parait destine aux memes fins que les siphons ou les glandes odoriferes observees dans plusieurs especes de Cheiropteres " %. These pubic warts, if Temminck's remarks be correct, present another very interesting secondary sexual character ; but, although I have examined a large number of specimens of Megaderma lyra and of various species of Rhinolophus preserved in spirit, I am unable to assert positively, as Temminck has done, that they are in no respect connected with the function of nutrition. To determine this question it would be necessary to examine recent specimens obtained during the season of lactation. Dr. Anderson, Curator of the Indian Museum, during a collecting-tour in Lower Bengal, obtained at Purneah a large number of specimens of the females of M. lyra with their young; and the following remarks occur in a letter received by me from him on bis return to Calcutta : - " All the young, even the largest, were adherent to the teats, some attached to the abdominal, and others to the pectoral * Descent of Man, vol. ii. p. 278. t Mr. Darwin enumerates many instances where he considers the brilliant colours of the fur or feathers of male animals, or other sexual peculiarities, are admired by the females. t Monographies de Mammalogie, vol. ii. p. 3. |