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Show 140 MR. F. E. BEDDARD ON THE POUCH AND [Feb. 3, variety of different types, shows that the transitory existence pouch in the young male is quite a common feature among Marsupials, especially perhaps among the carnivorous forms. A pouch was found in the young male Dasyurus ursinus up to the age of four months (its length being at that time 19*8 cm.), and one occurs in the young Acrobates pygmcea. A pouch was barely traceable in the young male Phalangista vulpina, just visible in a 4*6 cm. long Belideus breviceps, three weeks old. The adult males of these forms have of course no pouch nor trace of one. In Perameles nasuta there was a trace of a pouch discoverable in the young, but none in Halmaturus thetidis. The pouch is stated to open backwards in Dasyurus, as Owen says of Thylacinus and M M . Eydoux and Laurent of Perameles. It is evident from the paper to which I have referred, that the existence of a pouch, transitory or otherwise, among the male Marsupials is not confined to the carnivorous section of the Order, though apparently more commonly met with aud longer persistent among the members of that section. As the organ in the male Thylacine has not to my knowledge been illustrated, I have thought it desirable to have the accompanying drawing (p. 139) prepared. The figure shows the pouch, which was sketched by Mr. Smit immediately after the death of the animal, and the scrotum containing the testicles, which depends from the interior of the pouch. The drawing also shows that there is not merely a tract of naked skin surrounding the testes, but a deepish pouch which is overhung by the surrounding integument ; the pouch is deepest in front and gradually gets shallower behind; it follows therefore that the pouch is directed backwards as in Perameles. The general outline of the pouch is oval, or rather pear-shaped, for there is a narrow continuation of it backwards; the scrotum supported on a short stalk depends from the interior of the pouch nearer to the posterior than to the anterior extremity. The Brain. In order to injure the skull as little as possible, the brain was extracted in two halves, the skull having been sawn through the median vertical longitudinal plane. The brain was hardened in alcohol, and had a curious yellow colour not always seen in brains so prepared ; the brains of a Kangaroo and a Wallaby, which I had prepared for comparison with that of the Thylacine, were white ; on the other hand, the brain of a Sloth (also preserved in alcohol) showed the same brownish-yellow tint. The total length of the brain, measured from the end of the cerebellum to the -ulterior extremity of the olfactory lobe, was 76 millim. Greatest length of cerebral hemispheres 48 millim. Greatest height of cerebral hemispheres 26 millim. These measurements refer in all cases to the hardened brain. |