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DE. CLELAND ON THE EELATIONS 
Since the vomerine groove extends from the presphenoid to the intermaxillaries, it is 
obvious that the primary laminae of the vomer (its alee) can have no contact with the 
bones forming the back part of the palate. The articulation which the vomer forms 
usually with the maxillaries, and often with the palatals, is brought about by the pro- 
duction, downwards and backwards from the line of junction of the alee, of a mesial 
plate, which is an after-development, and of varying extent in different species. 
Between the vomer and the central plate of the ethmoid the only connexion that ever 
occurs is of a very secondary description. No doubt the appearances in human skulls 
are often such as would incline one to a different conclusion ; but in the skulls of other 
animals there is, even in the adult condition, in the majority of cases, no contact between 
the two bones at all ; and when there is, it is a contact of contiguity, not of continuity. 
The central plate of the ethmoid grows from above downwards at the expense of the 
septal cartilage, and is an ossification of that structure ; while, on the other hand, the 
vomer only embraces the cartilage, never invades it. 
But the most intimate and constant connexion of the vomer is with the lateral masses 
of the ethmoid ; although no one who had confined his attention to the arrangement in 
adult human skulls would think that these bones were at all related. This connexion 
can be very well seen in the Bog, the Cat, the Sheep, or the Pig. In all these animals, 
and indeed, as far as I am aware, in all mammalia except Man, the Orang, the Horse, 
the Elephant, and the Giraffe (keeping the Cetacea out of view at present), the vomer 
and lateral masses of the ethmoid form one continuous bone. The free superior edge 
of each ala of the vomer can be traced all the way back in contact with the mesial 
structures embraced ; and, forming a sharp angle with this edge when examined from 
above, but appearing to be gradually continuous with the ala when looked at from 
beneath, a very thin but often broad plate of bone passes outwards underneath the 
ethmoidal convolutions to the external inferior angle of the lateral mass of the ethmoid, 
and is continuous with the principal lamina which forms the framework of that bone, 
This plate is what I have called the ethmovomerine lamina. The vomer frequently 
extends some distance backwards beyond its junction with the ethmovomerine laminfe ; 
but the position of the latter is so far constant that their posterior edges are always in 
contact with the sphenoidal processes of the palate-bones. The place of junction of the 
ethmovomerine lamina and ethmoid always corresponds to the upper margin of the 
internal aspect of the foramen called in human anatomy sphenopalatine, but which has 
only a seeming relation to the sphenoid bone in the human subject, and none whatever 
in other mammals, and which it will be better therefore in this paper to call the nasal 
foramen of the palate-bone. 
The Vomer and Sjjhenoidal S'pongy Bones in Man. 
If we now proceed to examine the development of the vomer and the bones connected 
with it in the human subject, we shall see how beautifully the adult appearances are 
derived from conditions exactly corresponding to those just described. The key to these 
