ANATOMY OF TEE MANDRILL , 
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and there is an arrangement by which their general strength is increased, by a forking of the joint 
bearing processes which unite them together by the formation of a bony structure. These peculiarities 
connect the Mandrill, whose common position is on all-fours, with the inferior quadrupeds, for they 
exist in them. Then there is no true sacrum bone, but two or three back pieces (sacral vertebrae), 
form a short conical sacrum — one attached separately to the hip-bone on either side. This is like 
the arrangement in the Carnivora. The hip-bones are long, narrow, and deeply excavated behind, or 
rather externally ; the front of the bony girdle of the loins (the pelvis) is long ; and the bones (the 
ischial) on which the Mandrill sits are very broad and semicircular. Now, these three apparently 
simple matters of anatomical detail are not only of interest to those who recognise the analogies of the 
same parts in different animals, for they relate to means, to ends, and commend themselves to the 
YOUNG mandrill. (From a Sketch at the Zoological Gardens.) 
consideration of ordinary observers. The shape of the hip-bone on either side, so unlike that of man 
and the man-like Apes, perhaps the Gibbons excepted, depends upon the relation of the muscles which 
move the hind-quarters and their bones, and the hollow in the hip is well filled up by those which pass 
backwards to the thigh. The position of those muscles assists the motion of running on all-fours and 
of springing. The length of the girdle (the front of the pelvis or pubic bones) relates to the dimensions 
of the digestive and reproductive organs. The great size of the hauncli-bones, or rather of their ends, 
is due to their being covered by the great pad-like hard parts, or callosities, on which the creature sits 
y ery constantly. Instead of having the soft muscles so familiar to the human anatomist well and largely 
developed there, it has this mass of fat cellular tissue and coloured skin attached to a curved bone, 
the whole being a most comfortable seat, and very constantly used by this restless Monkey. The bones 
of the tail are few in number, for it is short, but the muscles which wag the organ in Monkeys, in 
which it is of some size, are still present at its root. There is a capacious chest in the Mandrill, but 
its bones, or rather the ribs which partly form it, are, as it were, pressed in at the sides, so that it is 
not round like that of the higher Apes, but rather long and flat at the sides, and thus resembles the 
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