Nos. IAND2.] ANATOMY OF SCOMBER SCOMBER. 245 



Cole makes reference (No. 15, p. 649), that the origin and ter- 

 mination of nerve fibers are the fundamental grounds for deter- 

 mining the homology of nerves. "The course of the nerves is of 

 less importance." Apparently in accordance with the same prin- 

 ciple Cole considers that the ophthalmicus profundus of fishes can 

 be found fused with the ophthalmicus superficialis. Of this he 

 says: "According to all reliable authority, the profundus is a 

 cutaneous sensory nerve; and Allis states, further, that in Aniia 

 it fuses with the superficial ophthalmic of the \^th. The latter 

 statement is interesting, when we consider that in ChiuKzra, as 

 well as in other cartilaginous fishes, the fusion is with the ophthal- 

 mic of the Vllth." The ophthalmicus profundus of Ainia, here 

 referred to, is the Portio ophthalmici profundi, carelessly called 

 "the ophthalmicus profundus" in my early work (No. 2, p. 513), 

 and not the ramus ophthalmicus profundus. This is an important 

 difference, for even admitting that the fibers that form the two 

 nerves have the same central origin and a similar peripheral dis- 

 tribution, they are certainly not the same nerves, for they are said 

 to be both found in a single fish, Polyptenis (Nos. 78 and 58). It 

 is, however, to be noted, that Pollard concludes that there is, in 

 the adult Polyptenis, no ramus ophthalmicus superficialis trig- 

 emini. In a 20-cm. specimen he says there appeared to be a com- 

 missure representing the nerve. 



Regarding the ciliary ganglion Cole says, in his complete work, 

 that a few ganglion cells are found on the inferior branch of the 

 oculomotorius at the point where the radix brevis joins that nerve, 

 and these cells alone are probably the homologue of the entire 

 ciliary ganglion described by Schwalbe in the same fish. 



The Trigemino-Facial Complex, the nervus profundus ex- 

 cluded, arises from the brain by two large roots, an anterior tri- 

 geminal one, and a posterior one which contains the facial and 

 lateral line components of the complex. The anterior root arises 

 from the ventro-lateral surface of the anterior end of the medulla, 



« 



at about the level of the hind end of the hypoarium. It thus lies, 

 at its origin, anterior to the hind end of the optic lobe, and ventral 

 to it. The posterior root of the complex arises from the lateral 

 surface of the medulla, immediately dorsal or dorso-anterior to 

 the root of the acusticus, in part from the tuberculum acusticum. 



