THE THEORY OF THE VERTEBRATE SKULL. 285 



sensory organ in which the vertebral — the auditory — nerve 

 loses itself, and, therefore, to be an organ as completely sepa- 

 rated from vertebral production as any other viscus, or as the 

 ball of the eye ; the deception lies only in this, that it is the 

 essence of this organ to be ossified, as it is that of the eye to be 

 crystalline. 



" The mastoid process is, in animals, and also in the human 

 foetus, a proper bone, in which the styloid process lies. It is 

 plainly inserted into the first vertebra, but it receives its signi- 

 fication from the tongue. 



" 2. Having entered so fully into the discussion of the first 

 cephalic vertebra, I might, except for clearness' sake, spare you 

 any delay over the second. But I will also demonstrate in this 

 how completely the brain-case is formed according to the idea of 

 a vertebra, and has eyen been partially produced as such. 



" In every skull of a foetus you may find the alee orbitcdes 

 of the sphenoid separate from it. They belong to the third 

 vertebra. But, in the half-developed foetus, the great wings 

 and the pterygoid processes are also separate from the body of 

 the sphenoid. The last-mentioned processes are foreign to the 

 sphenoid, and only coalesced with it ; they belong to quite 

 another formation, and very probably have the same significa- 

 tion as the os omoicleum of the Bird's head, as Cuvier has already 

 indicated. I shall return to them. 



" There remain, therefore, for the posterior sphenoid, or the 

 jaw vertebra, three portions of bone — the body and the great 

 wings, or the lateral and oblique processes of the vertebra. 

 The spinous processes are formed by the two parietals, which, 

 in many animals, coalesce so as to leave no suture, but are yet 

 originally two. It is to be remarked that, in the Sheep, this 

 vertebra is closed by the bones in question, without the inter- 

 mediation of the temporal, which also does not belong to the 

 vertebral group. The same occurs in the Chelonian, the 

 Crocodile, &c. 



" 3. Whoso has recognised the second vertebra, as such, need 

 only look at the third, especially in Kuminants, to discover 

 quite the same structure. The anterior sphenoid with the 

 aide orbitcdes represents the body, together with the lateral pro- 



