290 



Dr. J. C. Ewart. 



[Mar. 6, 



fundus) as the sympathetic ganglia of the trunk stand to the spinal 

 nerves, and that the ciliary ganglion may henceforth be considered a 

 sympathetic ganglion. Further investigations may show that the 

 ganglia in connexion with the branches of the trigeminus (fifth) 

 nerve may also be considered as belonging to the sympathetic system. 

 In conclusion, I may say that I have found the vestiges of the ophthal- 

 micus profundus ganglion in a five months human embryo lying under 

 cover of the inner portion of the Gasserian ganglion, and satisfied my- 

 self that the ophthalmicus profundus of the Elasmobranch is repre- 

 sented in man, as suggested by several writers, by the so-called nasal 

 branch of the ophthalmic division of the fifth. To, as far as possible, 

 clear up the confusion that has arisen from mistaking the ophthal- 

 micus profundus nerve for a branch of the oculo-motor or of the 

 trigeminus nerve, and the ganglion of the ophthalmicus profundus 

 for the ciliary ganglion, it might be well in future to speak of the 

 profundus as the oculo-nasal nerve and its ganglion as the oculo-nasal 

 ganglion. 



IY. " The Cranial Nerves of the Torpedo. (Preliminary Note.)" 

 By J. C. Ewart, M.D. Communicated by Professor M. 

 Foster, Sec. U.S. Received February 13, 1890. 



The cranial nerves of the torpedo agree in their general arrange- 

 ment with those of the skate.* The ophthalmicus profundus occu- 

 pies the usual position, but its ganglion lies in close contact with the 

 Gasserian, and not on a level with the ciliary, ganglion. The trige- 

 minus has the usual distribution, for, notwithstanding the statements 

 in the most recent text-books,f the trigeminus sends no branch to the 

 electric organ. The facial complex includes the superficial ophthal- 

 mic, the buccal, and the hyomandibular nerves, all of which have the 

 same distribution as the corresponding nerves in the skate ; but the 

 hyomandibular includes or is accompanied by a large bundle of nerve 

 fibres which supply the anterior and inner portion of the electric 

 organ. This large nerve cord (the first electric nerve) has hitherto 

 almost invariably % been described as a branch of the trigeminus. When 

 traced backwards, it is found to spring from the anterior portion of 

 the electric lobe. 



* Ewart, "On the Cranial Nerves of Elasmobranch Fishes," 'Roy. Soc. Proc.,' 

 vol. 45, 1889. 



f E.g., McKendrick, ' Text-Book of Physiology,' 1888, and Wiedersheim, 

 ' Grundriss der vergleichenden Anatomie,' 1888. 



X Eritsch is the only author I am acquainted with who does not describe the first 

 electric nerve as a branch of the trigeminus (' Untersuchungen uber den feineren 

 Eau des Fischgehirnb,' Berlin, 1878) ; he, however, speaks of it as being contiguous 

 to, and as disappearing along with, the nervus trigeminus. 



