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Show 712 MR. F. G. PARSONS O N T H E [June 16 does not enter the sciatic trunk, joining the 2nd sacral; it supplies the pelvis and perineum. The great sciatic nerve leaves the pelvis through the great sciatic foramen, passing superficial to the pyriformis; just before reaching that muscle it gives off a large nerve to the hamstrings, which passes deep to the pyriformis and supplies the posterior biceps, semimembranosus, semitendinosus, and the ischio-femoral. In the upper third of the thigh the great sciatic gives off the short saphenous which supplies the skin of the outer side of the leg from the knee to the ankle. About the middle of the thigh the sciatic divides into external and internal popliteal branches, the former of which winds round the outer side of the head of the fibula, where it divides into themusculo-cutaneous and branches to supply the peroneal and extensor groups of leg-muscles. The musculo-cutaneous runs down the outer side of the leg and divides at the ankle into an outer and an inner branc'.; the outer of these supplies the cleft between the fourth and fifth toes as well as the outer side of the fifth, the inner goes to the inner side of the large fourth toe as well as to the two small inner toes, that is to say to the second, third, and half the fourth toes, the first toe being absent. It will thus be seen that there is no anterior tibial nerve in the Kangaroo, a fact which might be predicted when one remembers that there is no cleft between the first and second toes nor any extensor brevis digitorum muscle for it to supply. The internal popliteal nerve gives off branches for the gastrocnemius, plantaris, popliteus, and rotator fibula?; it passes through the popliteal space and runs down, between the superficial and deep muscles of the calf, to the back of the internal malleolus, being unaccompanied in the leg by any artery. Soon after passing the internal malleolus it gives off a small deep branch to the muscles of the sole, which apparently corresponds to the greater part of the human external plantar nerve. After this the main trunk supplies the plantar surfaces of all the four toes, the branch for the outer one and a half coming off in the anterior part of the sole and passing deep to the plantar fascia. Digestive Sgstem. The roof of tbe Hard Palate has eight transverse ridges, the anterior two of which are curved, with the convexity forwards. In the anterior half of the palate there are many tubercles between the ridges, a condition which has been described by Flower in the Didelphyidae l. The Soft Palate is smooth on both its nasal and buccal surfaces ; it ends posteriorly in a deep sharp notch, and there is no sign of a uvula. The Tongue has four transverse ridges rather behind the centre of the dorsum. There are backwardly directed filiform papillae all over the surface, while the fungiform papillae are best 1 Lectures on the Comparative Anatomy of tbe Organs of Digestion ot tbe Mammalia, College of Surgeons, 1872, Lecture XII. |