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HOMOLOGY OF PALATINE PROCESS, 
investigation by Mr. R. H. Burne that the palatine process is 
distinct from the premaxillary in an embryo Rabbit as large as 
8 cm. Furthermore, Albrecht and Sutton have both maintained 
that the palatine process is a distinct element from the pre- 
maxillary proper, though owing to their evidence being largely 
pathological their views have not been generally accepted. Sutton 
holds that the palatine process is the homologue of the " vomer " 
of the Ichthyopsida, and that the mammalian vomer is represented 
by the parasphenoid in the lower forms. Whether he is correct 
or not in his Ichthyopsidian homologies I am not in a position to 
definitely determine; but I think there is very strong evidence in 
favour of the homology of the mammalian palatine process of the 
premaxillary with the so-called " vomer " of at least the lizard 
and snake, and in the present paper I shall bring forward a few 
facts from Comparative Anatomy and Embryology in favour of 
such a view. 
For some time I have been engaged in the study of the compara- 
tive anatomy of J acobson's Organ, and having studied the anterior 
nasal region of a very large number of mammals and reptiles by 
means of microscopic sections, I have come across a number of 
interesting facts in connection with the present subject. 
In mammals the organs of Jacobson, as is well known, are 
supported by the "recurrent cartilages" — developments of the 
trabecular cornua, and as the cartilages are almost invariably 
developed to a similar degree to the organs, the close connection 
between the two is manifest. Furthermore, the cartilaginous 
framework of each organ rests on a bony support curved to fit the 
cartilage, and which is almost invariably anchylosed to the pre- 
maxillary forming its palatine process. When the organ of 
Jacobson is well developed and much elongated, its bony support 
is correspondingly long, while when the organ is rudimentary the 
palatine process is short or absent. So that not only is there a 
close connection existing between the organ and the cartilage, but 
also an intimate association between the cartilage and the 
supporting bone. 
