362 MR. R. OWEN ON THE OSTEOLOGY OF 
of the Orang wants the knob at the back part of the ring which is observable in Man ; 
it presents here merely a roughness of the surface. The spine of the dentata has a 
ridge along its upper part, and its extremity is slightly bifurcate; the spines of the 
other cervical vertebre are simple; that of the fifth is the longest ; those of the sixth 
and seventh have a slight inclination towards the head, indicating that the centre of 
motion in this region of the vertebral column is nearer the head than in Man. The 
transverse processes of the fifth and sixth, especially the latter, are longer, and inclined 
more forwards and downwards than in the Chimpanzee or in Man. The whole of the 
cervical region is proportionally shorter than in Man, and consequently better adapted 
to support the head. 
The entire vertebral column has one general curve dorsad from the atlas to the com- 
mencement of the sacrum, where there is a slight curve in the contrary direction. 
The number of the dorsal or costal vertebre in the Orang is twelve, as in the human 
subject. This is one of the more important differences between the Orang and Chim- 
panzee: the number in the latter animal, as previously noticed, being thirteen, 
The number of the lumbar vertebre is four, as in the Chimpanzee. This, at least, is 
the case in the skeleton of the Pongo preserved in the Museum of Comparative Ana- 
tomy in the Garden of Plants at Paris, and in the trunk of the skeleton of the adult 
Orang in the collection of the Zoological Society ; in which latter specimen, as the 
bones are connected by their natural ligaments, there is no room for supposing a ver- 
tebra to have been accidentally lost. This fact it is the more necessary to state, be- 
cause the skeleton of the Pongo in the Museum of the College of Surgeons in London 
differs from those above mentioned in having an additional lumbar vertebra; and as the 
skeletons of the young Orangs have uniformly presented but four lumbar vertebre, 
some stress has been laid on the additional vertebra of the above specimen of Pongo, 
as indicative of its specific difference from the young Orang!. The additional lumbar 
vertebra in the College specimen indicates, however, its abnormal character by its form 
and situation: it is lodged deeper in the interspace of the ossa innominata than the last 
lumbar vertebra of the adult Orang in the Museum of the Zoological Society ; and the 
right transverse process is expanded like that of a sacral vertebra, and is joined to the 
ilium in a corresponding manner. The human subject occasionally presents a similar 
lusus of an additional lumbar vertebra; and in the skeleton of an Australian native, 
where the number of lumbar vertebre is normal, I have also observed that the last has 
the left transverse process similarly expanded and joined to the ilium, as has been de- 
scribed in the Orang. The lumbar vertebre have much shorter spines in the Orang than 
in the Chimpanzee. 
The sacrum deviates from that of Man in the same particulars as in the Chimpanzee, 
but is longer, narrower, and straighter. In counting the vertebre of this part, I have 
been guided, as in human anatomy, by the circumstance of their being perforated for 
1 See Dr. Harwood’s paper, Linnean Transactions, vol. xv. p, 473. 

