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organs in the occipital region. I find that it also gives off 
fibers to the digastric muscle . A short posterior branch 
seems to be distributed solely to the digastric muscle. The 
the small second vagus trunk seems to be the one described 
by Kingsley as arising from the posterior surface of the 
glossopharyngeal trunk and designated by him tentatively 
as the supratemporalis. I find that it arises from the 
ganglion entirely independent of the glossopharyngeal. 
It contributes most of the fibers of the combined nerve 
above mentioned. It probably corresponds to the branches 
supplying the sense-organs in the occipital region in Cryp- 
tobranchus as described by McGregor,* and considered by 
him as possibly representing the ramus supratemporalis. 
A little posterior and ventral to the emergence of Jacob- 
son’s commissure from the ganglion arises a trunk (3) that 
soon divides into glossopharyngeal nerve proper and the 
first branchial nerve. This account of the first three nerve 
trunks differs decidedly from that given by Kingsley. 
.According to him Jacobson’s commissure and the glosso- 
pharyngeal nerve arise by a common trunk, and the first 
branchial nerve leaves the ganglion as a separate trunk 
distinct from the glossopharyngeal. I find that Jacobson’s 
commissure and the glossopharyngeal-branchial trunk 
both derive a portion of their fibers from the brain 
through the second vagus root, but they emerge from the 
ganglion distinct from each other, but very close together. 
The second branchial nerve (4) arises from the ganglion 
near its dorsal border close to the origin of the trunk 
termed provisionally the supratemporalis. The third 
branchial nerve (5) according to Kingsley arises with the 
second from a common trunk. I find that it leaves the 
lateral border of the ganglion some distance ventral to the 
emergence of the second branchial nerve and remains 
distinct from it. The ramus lateralis superior^ arises 
close to the origin of the third branchial nerve, and as 
noticed by Kingsley ventral to the origin of the ramus 
lateralis medius. Leaving the ganglion the ramus latera- 
* McGregor, J. H. —Preliminary Notes on the Cranial Nerves of Cryptobranehus 
Alleghaniensis. Journ. Compar. Neurol., Vol. VI, No. 1, 1896. 
