GANGLIA OF RANA 463 
the’ dorsal and mesial portion of the ganglion. It extends ven- 
trally as a distinct ganglionic mass about two-thirds of the total 
dorso-ventral diameter of the combined Gasserian and profundus. 
The ramus ophthalmicus (O. V., fig. 1) seems at this time to come 
entirely from the profundus portion, though doubtless there are 
fibers in this ramus derived from the ventral portion or Gasserian 
ganglion also. This nerve evidently contains later, if not at this 
time, the representatives of both the ophthalmic V and of the 
opththalmicus profundus of the ganoids. The distinctness of this 
ganglion confirms the position taken by Wilder (92, p. 172) and 
confirmed by Strong (95, p. 173), that the ophthalmicus pro- 
fundus nerve has fused with the ramus ophthalmicus V and that 
probably in higher types the profundus ganglion is fused with 
the Gasserian. 
The infra-orbital trunk arises from the ventral border of the 
Gasserian ganglion and immediately splits into the r. maxillaris 
and the r. mandibularis. Smaller twigs described by Strong 
could not be positively identified. The apparent difference 
between the point of origin of nerves in this complex in the 8 mm. 
tadpole as compared with Strong’s description, is due to the fact 
that in the older tadpole the head becomes flat, thus altering the 
position of the origin of nerves. | 
Aside from the difference noted below, the ganglia and nerves 
of the 8 mm. tadpole conform closely to the description of Strong, 
whose findings we confirm in every detail except that some of 
the more minute branches could not be located in our material. 
It should be noted here that Strong’s nomenclature is followed 
throughout in this paper. 
The most striking feature in the arrangement of the V + VII 
complex is the dorso-ventral elongation as compared with similar 
stages in Ameiurus (Landacre 710) and Lepidosteus (Landacre 
12). This is probably due to the fact that it is crowded between 
the eye and the ear so that the long axis of this ganglion as well 
as of [IX + X hes at right angles to the long axis of the body. 
It will be noticed in figure 1 that the special visceral or gustatory 
portion of the geniculate ganglion could not be identified. This 
is in marked contrast to Lepidosteus at a similar stage of growth. 
