56 Traces of Unity in the 



for its oblique spinous processes, the "partes condyl- 

 oidae " for its laminae, the crista occipitalis for its 

 spinous process, the pars basilaris for its body, and 

 the foramina for its intervertebral foramina. The jaw- 

 vertebra has for laminae the parietal bones, and for body 

 and transverse processes the posterior sphenoid. The 

 eye-vertebra has for its laminae the frontal bones, and 

 for its body and transverse processes the anterior 

 sphenoid. At the time of the delivery of this lecture, 

 Oken saw no more than these three vertebrae in the 

 skull ; at a later period he also saw, in advance of the 

 eye-vertebra, the rudiment of a fourth vertebra, of which 

 the vomer is the body, the lachrymal bones the laminae, 

 and the nasal bones a bifid spinous process. Without 

 doing more than merely turning a skull like that of a 

 lamb round, and looking at it attentively on all sides, it 

 is easy to see that the case may be as Oken put it : by 

 removing the bones which take no part in the formation 

 of the " basis cranii," i.e. the frontals, the parietals, the 

 temporals, the lachrymals, the orbitals, the nasals, and 

 the aethmoids, and by then replacing them, the difficulty 

 is to avoid seeing that it must be so ; for on removing the 

 bones, and looking from above, the basis cranii is evi- 

 dently a prolongation of the bodies of the vertebral 

 column into which at least three vertebrae may enter, 

 and on replacing them the cavity which is thus arched 

 over, is as evidently an expanded portion of the verte- 

 bral canal. 



Oken also saw very clearly that the " pars petrosa " 

 of the temporal bone is related to the third vertebra in 

 the same way as that in which the jaw and the eye are 

 related to the two other vertebrae that it was, not a 

 part of the actual vertebral zone, but a sense-organ 

 (Sinnorgan), the eyes, jaws and ears being all essentially 



