712 MR. F. G. PARSONS ON THE [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 the musculo-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 branch; the outer 
ot 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 beng 
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 gastrocne- 
mius, plantaris, popliteus, and rotator fibule ; 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 System. 
The roof of the 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 deseribed by 
Flower in the Didelphyide *. 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 
papille all over the surface, while the fungiform papilla are best 
* Lectures on the Comparative Anatomy of the Organs of Digestion of the 
Mammalia, College of Surgeons, 1872, Lecture XII. 
