136 E. C. CASE 
that it did not exist. Moreover, there is a decided difference 
in the endocranial casts in this region. In Belodon and Diadectes 
the processes are large and rise from the sides of the epiphysis, 
in Desmatosuchus they are small and are entirely anterior to 
the epiphysis. It is possible that if a true cast of the brain could 
be obtained the origin of the processes might be found “to be 
the same in all, but as the casts were all made from empty 
cavities a similar origin should be apparent. ' 
The epiphysis is very different in form. In Belodon and 
Diadectes there is a strong posterior process, and Cope describes 
the epiphysis of the former as ‘subquadrate.’ The orbitopineal 
process extends either directly outward from the side, Diadectes, 
or outward and forward, Belodon. In Desmatosuchus the 
epiphysis is erect and narrow anteroposteriorly with no posterior 
process. In both Belodon and Desmatosuchus the processes 
referred to as the epiphysis are casts of a deep pit on the under 
side of the skull in the exact position of the pineal foramen in 
other reptiles, but in neither of these is the roof perforated. . In 
looking up this matter the author has found that much uncer- 
tainty exists as to the exact character of this process in the brain; 
it is known that both the epiphysis and the paraphysis may reach 
large size and that either one may terminate in a functional 
eye; at least, either one may carry organs which possess the 
histological structures of the retina and the crystalline lens. 
In some forms there has also been found a third evagination of 
the brain, posterior to the epiphysis, called the pineal organ, 
which has a similar histological structure. Wilder, in his History 
of the Human Body, states that it is the paraphysis which was 
developed in the extinct Stegocephalia and filled the parietal 
foramen and the epiphysis which was developed in the reptiles, 
birds, and mammals. On the other hand, it is known that the 
epiphysis is not developed in the modern alligator. The term 
epiphysis is used in this paper only in a general sense and without 
knowledge of its true nature. 
On the lower side of the diencephalic region of the cast is the 
second process; this represents the combined infundibulum and 
the saccus vasculosus, or the pituitary body. Only the posterior 
