CRANIAL GANGLIA OF SQUALUS ACANTHIAS 
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rises the lateral line component of the auricular ramus. The 
third ganglion and the remaining fibers from the second ganglion 
form the main lateralis trunk. I fail to find a distinct root or 
ganglion for the small general cutaneous element in the vagus. 
Its fibers are distributed with those from the first two lateral 
line ganglia, a few entering the supratemporal X and the major 
part uniting in approximately equal portions with lateral line 
fibers to form the auricularis X. The visceral roots of the Xth 
extend for a long distance postero-dorsally along the medulla 
wall. In the specimen studied there is a series of seventeen 
visceral roots. The majority of these are mixed, comprising a 
wide sensory strand and a small onotor strand. The posterior 
(4) roots are all motor. The motor fibers arrange themselves 
in fairly definite strands and are traceable through the large 
fibrous root of X to their distribution in the branchial and 
visceral nerves. The visceral X ganglia show a segmentation into 
four branchial and one intestinal divisions, all more or less in 
contact, and the last two quite fused. The cervical plexus is 
composed of the two occipital nerves and a large motor and a 
small sensory element from each of the first three spinal nerves. 
Though closely in contact with the vagus for some distance there 
is no interchange of fibers. 
Department of Zoology, 
Grinnell College. 
