THE FOREBRAIN OF THE ALLIGATOR 329 
Many workers have indicated the presence of an epiphysis 
in the alligator brain. The work of Albert Reese (10) has shown 
the structure so named is a paraphysis and that no epiphysis 
is present in the alligator, even in the embryo. In 1908, Reese 
published an account of the general embryological development 
of Alligator mississippiensis. 
No attempt will be made to review systematically the ex- 
tensive literature on the brains of reptiles in general, though 
references to this literature will be made as occasion may 
arise. Among the classical descriptions of the rept lian brain 
especial mention should be made of the valuable descrip- 
tion and figures of the turtle brain published in 1895 by Mrs. 
Susanna Phelps Gage, in commemoration of whose important 
contributions to comparative neurology the current volume of 
The Journal of Comparative Neurology is dedicated. 
CELL STRUCTURES 
The positions of the nuclei of the telencephalon, with such 
details of their cell arrangement and cell structure as have been 
observed, will first be described, together with some more frag- 
mentary observations on the diencephalic nuclei. Then using 
these facts for orientation, the courses and connections of the 
fiber tracts will be considered. 
Olfactory Bulb 
Johnston (’13) described the presence of a nervus terminalis 
in the reptiles. The preparations available are not suitable 
for the identification of this nerve in the alligator. 
The cell bodies of the peripheral olfactory neurones lie in the 
olfactory epithelium of the nasal cavity. Their axones pass 
back as fibers of the olfactory nerve or ‘fila olfactoria.’ These 
fibers are unmyelinated and, after a very short course, enter 
the olfactory bulb. In its outer portion they break up into ter- 
minal arborizations which form synapses with dendrites of the 
mitral cells (figs. 23 and 24) and with other receptive cells of 
the olfactory bulb. 
