GANGLIA OF RANA 465 
The exact relation of the various ganglia in the [IX and X as 
figured in plots 1 and 2 to the ganglia shown in Strong’s plot 
is not always easy to determine. 
There can be little doubt, however, that the glossopharyngeal 
ganglion is identical with ganglion C' of Strong’s plot which occu- 
pies the extreme anterior end of the IX and X complex. It is 
hard to conceive of the IX ganglion of our plot being combined 
with X so as not to bring the IX into the position occupied by 
ganglion C. 
The appearance of the IX ganglion in plots 1 and 2 is strikingly 
similar to that of Menidia (Herrick ’99), and of Ameiurus (Land- 
acre 710) and Lepidosteus (Landacre 712) of approximately the 
same stage. 
In the 8 mm. stage there is only one nerve arising from the 
visceralis IX. This is the ramus lingualis of Strong and runs 
forward on the outer surface of the thymus gland. In the 10 
mm. stage (fig. 2) there are two rami arising from the anterior 
end of the ganglion, the larger one running down and forward on 
the outer surface of the thymus gland, the ramus lingualis, and a 
smaller, the ramus pharyngeus, which runs down and forward on 
the inner surface of the thymus gland. We have been able to 
detect no trace of the ramus communicans IX ad VII at this 
stage in either the 8 mm. or 10 mm. embryo. 
In the 35 mm. larva there are three nerves arising from the 
anterior end of the IX ganglion. Two of them, corresponding 
to the ramus pharyngeus and the r. lingualis of Strong’s plot, 
undoubtedly arise from the cells of the ganglion, since the fibrous 
bundles disappear in the ganglion. The third nerve corresponding 
to the communicating nerve from IX to VEI apparently does not 
arise from the ganglion but runs back on the dorsal surface of the 
ganglion without diminishing in size and passes into the X gan- 
glionic complex. Its behavior in passing the visceral LX ganglion 
furnishes strong evidence that it is probably not visceral but 
purely cutaneous as Strong describes it. 
Of the two visceral nerves, the ramus lingualis is much the 
larger. It arises from the anterior end of the ganglion and pur- 
sues a course downward and forward on the outer surface of the 
THE JOURNAL OF COMPARATIVE NEUROLOGY, VOL. 22, NO. 5 
