480 
HOMOLOGY OF PALATINE PROCESS, 
distinction between this bone and the palatine process of the 
premaxillary he has involved himself in contradiction. In his 
beautiful sections of the head of the foetal Tatusia he shows the 
supporting bones of Jacobson's cartilages, and in his description 
of section 7, says : — " The cartilages [protecting Jacobson's organs] 
themselves have an osseous counterpart protecting them on the 
inner side and having their shape and direction; these are the 
anterior paired vomers (v'), bones well known for their large 
development in the Ophidia and LacertUia" He further recog- 
nises that these are not parts of the true vomer, and evidently 
considers them as quite distinct from the premaxillary. In his 
description of the head of the young JSrinareus, he further refers 
to the intimate association of the recurrent cartilages -and their 
supporting bones or anterior paired vomers. In referring to the 
recurrent cartilages as seen in the dissected skull of the young 
embryo, he says : — " Each leafy part is supported by a bone the 
form of which it dominates, so that each tract is also hollow on 
the face that looks towards the curved inner edge of the cartilage; 
it lies on the inside, back to back to its fellow : these are the 
front paired vomers, and answer to the paired vomers of the 
Snake and Lizard among the Reptiles." These bones which he 
calls " anterior paired vomers " are almost without doubt the parts 
which, becoming anchylosed with the premaxillaries, form their 
palatine processes. Parker, however, seems to consider that there 
are palatine processes in addition to the anterior vomers, but 
as the cartilages of Jacobson at their anterior part are in contact 
with the body of the premaxillary there is really no space for a 
palatine process distinct from the ossification in connection with 
Jacobson's cartilage, and if in any form there appears to be a 
palatine process in addition to an anterior vomer it is probably 
due to the anterior portion of ossific tract of Jacobson's cartilage 
becoming ossified by invasion from the premaxillary. 
A study of the comparative anatomy of the prenasal region 
gives very strong confirmatory evidence that the bone supporting 
the cartilage of Jacobson is not morphologically a part of the 
premaxillary, though generally anchylosed with it. 
