ANATOMY OF THE BABOON. 
135 
each, other, so as to produce a decided angle. This is slightly seen in the Orangs, but it is very evident 
indeed in the Baboons. On the contrary, there is no angle formed in the Gorilla and Chimpanzee. 
Again, in man, the sacrum bone is curved, the hollow of the bend looking forwards. This is the case 
in the Baboon and also in the Siamang ; but the curvature is much less in the great Apes or 
Troglodytes; furthermore, this sacrum bone is relatively very broad in the Baboon. 
Now, these are not simply anatomical curiosities, and they are really of some interest to the 
youngest naturalist who cares to try and puzzle out what these things really mean. Either they 
have a meaning or they have not. 11 they are freaks of Nature or the results of chance, then there is 
nothing more to be said ; or if they are deeply connected with the method of life or the habits of the 
creatures, they may be said to have been given for a purpose. But the notions about chance and 
freaks belong to a bygone age, for Nature works neither by accident nor by impulses, but by law. 
So there must be some meaning in these things, and the key to their comprehension is the gradual 
change of form and ox structure which has been undergone in the long ages during which 
one animal has become altered so as to depart greatly from the parent stock, and to assume what is 
called a new specific shape — to become a new kind. And in the new kind there are relics of the old 
form — pieces of bone here and there ; muscles, tendons, or useless teeth, , and such things, which 
are, as it were, part of the coat-of-arms to enable the genealogist to trace the history of the family. 
In the Baboons there- is a curious condition of the first bone of the neck (the atlas, or first 
vertebra, on which the head rests). It is a massive ring of bone, down the centre of which the great 
nerve (spinal cord) of the spine passes, and it becomes stouter with ago, and the central hole is all the 
smaller. It lias a small spinous process, to which there is a muscular attachment, which tends to 
keep up the heavy skull and long nose. A good short back-bone, not over pliant, is necessary to 
the Baboon, and a provision is made in order to produce this ; for the bodies of the vertebra? are 
found to be larger and longer .as they are further down the spine. This is what occurs in man 
and in the Gibbons, but it is only slightly noticed in the higher Apes — the Troglodytes and Orangs. 
The Baboon may be sai l to have sometimes only eighteen back and loin vertebra?, and twelve or 
thirteen are rib-bearing, and the spines of these bones are strong and often expanded or flattened at 
their ends ; moreover, the last spines project forwards and the others backwards. All this arrangement 
is especially ape and animal-like, and refers to the st rough toning of the muscles used in moving on 
all-fours. There is of course a tail to be considered, and in the shortest there arc from five to eight 
bones, or modified vertebra 1 , and whether short or long, tlic muscles of the tail are all to be met witli 
at its root. 
Such clever animals ought to have well-formed brains, and yet not so elaborately constructed as 
those of the Anthropomorpha, whose movements are more varied, and who can walk erect for a longer 
or shorter time. It is found that the brain of the Baboon, although less complicated, or rather less 
perfectly formed, than that of the Chimpanzee and Orang, is singularly like those of the Guenons 
and Macaques in the surface markings and convolutions, and, in fact, the brains of these animals agree 
in all essential points. The principal convolutions and fissures which are noticed in the Troglodytes 
exist, but the external perpendicular fissure is strongly marked, and all the little brain is covered by 
the cerebrum, or brain proper. 
There is no mistaking a Baboon’s skull ; it is large for a Monkey, and the face part is always one- 
half ot the whole, the brain case being cast in the shade, as it were, by the huge upper and lower jaws, 
and their fine armament of teeth. In old males the length of face is much greater than one-half, 
and the front of the upper jaw is stuck out considerably. But in all there is a swelling of the upper 
jaw-bone, just in front of the orbit and on either side of the nose bones, which sometimes is vast and 
at others turned into a ridge. It is this which is covered by the curious tints and colours in some. 
The jaws seem pinched in, just above the upper grinding teeth, and then conies this swelling. Strong 
teetli exist in the upper jaw, and the canine, or eye teeth, more than an inch in length, are long, 
slender, curved, and sharp. The front or incisor teeth are large, the middle ones being the largest, and 
che three grinders have sharp projections on them which are not readily worn. As the eyes are 
close together, the orbits are only separated by the forehead (frontal) bone and the united nose-bones 
These cavities are, moreover, broad, and look a little outwards, and they open into tie 
strange swollen, muzzle. The 
ridges over 
the orbits are great, and the opening for the nose is 
