viii Journal of Comparative Neurology. 



gives off, just distal to its ganglion, a slender dorsal branch which soon 

 bifurcates and is distributed to the skin of the occipital region. Vagus 

 3 presents some further variations which need not be noted here. Its 

 post-branchial supplies the eighth or last demi-branch. The intestinal 

 division of the vagus arises as its most posterior root and soon after 

 leaving the cranium expands into an obvious ganglion. It splits up 

 forming a plexus on the pharynx and proximal part of the oesophagus. 

 Some bundles reunite and again break up to form a plexus on the distal 

 part of the oesophagus and the stomach which was traced as far as the 

 spiral valve. Both plexus lie on the circular muscles of the oesophagus 

 and stomach, beneath the pigmented serous coat. A very slender 

 nerve was with much difificulty traced on to the wall of the sinus veno- 

 sus and this was the only cardiac branch of the vagus found. 



To the description of the intestinal nerve is appended an interest- 

 ing discussion of Shore's results on the vagus of the skate. Shore's 

 views, which follow Gaskell's lines, probably require some revision in 

 view of the results of researches upon the sympathetic and cerebro- 

 spinal ganglia by means of the Golgi and Ehrlich methods. It is 

 interesting to note that here also we find a somatic cutaneous branch so 

 that the vagus cannot be regarded as purely splanchnic (excluding, of 

 course, the lateral line system). This somatic element has been shown 

 to be present in some amphibia, in certain teleosts by Herrick and, 

 further, Kingsbury has shown that in the medulla of several teleosts we 

 have certain contingents separating from the spinal V and passing out 

 with vagus roots, thus indicating the probable existence of cutaneous 

 branches. The writer of this review can, from his own observation, 

 add Hiatula onitis to this list. 



The anterior spinal nerves have no dorsal roots and pass through 

 the cranium. There are numerous rootlets which unite into two main 

 nerves, emerging by three foramina. These two nerves unite to form 

 the brachial nerve. The first " cranial spinal, " as these two nerves 

 are termed, arises by seven rootlets which unite just outside the cranium 

 and sends a dorsal branch up to the skin. The second cranial spinal 

 arises by six rootlets which form two roots which remain in the main 

 distinct but interchange fibers just outside the cranium, at which point 

 two dorsal branches are given off to the skin. The brachial nerve 

 formed by the union of these two cranial spinal nerves is distributed to 

 the pectoral fin and sends a branch to the muscles of the last or fifth 

 branchial arch. 



In his discussion of the independent character of the lateral line 

 system, Cole marshals the arguments in favor of this view more clearly 



