344 Kneeland on the Skeleton of the Great Chimpanzée. 
surface for the humerus, on account of the less prominence 
of the inner ridge of the trochlea, differs from that of man in 
being proportionally wider, and in having a deep concave 
inner wall, which in the human ulna is not only wanting, but 
the edge of this border of the joint is worn into a deep notch 
corresponding with the long inner ridge of the human tro- 
chlea; at the bottom of this cavity is an irregular long bone, 
apparently wedged in, and perhaps having a separate centre 
of ossification ; if the olecranon process were taken off through 
the suture here left open, the head of the ulna would very 
much resemble the head of the tibia, to which it corresponds 
in the lower extremity ; this is seen on both sides. The 
articulating surface for the head of the radius is less perpen- 
dicular than in man; the coronoid process is also less promi- 
nent, in conformity with the small anterior concavity on the 
humerus ; the styloid process, and the accompanying groove; 
occupy a greater proportion of the lower extremity. With 
the exception of stronger ridges, and sharper angles, the 
remaining portions of the ulna and radius resemble much the 
same bones in man, on a large scale. The proportion between 
the humerus and ulna brings this animal nearer to man than 
the Chimpanzée or Orang. 
The femur, in its head and neck, is much like the human; 
it has a roughness, hardly a depression, for the ligamentum 
teres; the neck of the bone is proportionally shorter, and 
placed more obliquely with respect to the shaft; the trochan- 
ters, especially the great, are much stronger ; the lesser tro- 
chanter also stands out enormously to receive the internal 
iliac muscle, situated in the immense iliac fossa, and princi- 
pally concerned in flexing the thigh on the pelvis, as in the 
act of climbing ; the space between the great trochanter and 
the head of the bone is less, and the concavity much deeper 
than in man ; the neck of the bone is also more flattened and 
less round, supporting, as it does, less proportional weight. 
The whole bone is flatter, especially just above the condyles, 
and its shaft more curved. Though the inner condyle is s0 
