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the outer end of which is traversed by a channel or canal that gives 

 passage to the nerve here under consideration. Having traversed this 

 short canal, and having reached the ventro-mesial aspect of the ramus 

 ophthalmicus, the nerve runs forward and upward between the ophthal- 

 micus and the side wall of the nasal capsule, sending branches to the 

 capsule, certain of which perforate the nasal cartilages, while others pass 

 inward between them. It could be traced forward slightly beyond the 

 capsule. It seems to be quite certainly the ramus nasalis of the ophthal- 

 micus trigemini of Müller's descriptions (nerve 5" of his figures), but 

 Müller says that that nerve passes dorsal to the opticus, and that it is 

 distributed to the nasal tube beginning close in front of the nasal 

 capsule. The corresponding nerve in Myxine is said by Fürbringer 

 to run forward under the opticus, as I find it in Bdellostoma. Müller's 

 description of its course is thus probably erroneous. 



The nerve of my adults would seem to be the branch h of the 

 nervus ophthalmicus of v. Kupffer's descriptions of embryos, but it 

 certainly, in the adult, arises from the maxillo-mandibularis ganglion, 

 and not from the ophthalmicus ganglion. Its position ventral to the 

 optic nerve, its general course, and its distribution to the nasal cap- 

 sule, seem to indicate that it probably is the homologue of the ramus 

 palatinus anterior trigemini of Amia; but that nerve of Amia lies 

 ventral to the chondrocranium, while the nerve in Bdellostoma lies 

 dorsal to the palatine. This so-called palatine is, however, quite 

 undoubtedly an anterior portion of the trabecula, and not a palatine 

 at all; and the nerve in Bdellostoma could readily acquire a position 

 ventral to this cartilage by simply slipping downward between it and 

 the membranous cranium, and thus agree, in position, with the nerve 

 in Amia. The short membranous canal that the nerve traverses shortly 

 after it issues from the trigemino- facialis chamber would then be 

 simply the distal end of a relatively long cranial canal that the nerve 

 traverses in passing from the trigemino-facialis chamber to the ventral 

 surface of the cranium; and in Scomber (4) the ramus palatinus 

 facialis traverses just such a canal. 



The ventral branch of the palatinus trigemini runs forward, with 

 the dorsal one, across the so-called thick lateral process of the trabe- 

 cula, but it passes ventro-mesial to the membranous process traversed 

 by the dorsal nerve. It then turns forward, downward and mesially, 

 through the hind end of a space between the palatine cartilage and 

 a short bar or process of cartilage not given by Ayers and Jackson 

 in their descriptions of the fish. This bit of cartilage is usually a 

 short process, i j 2 mm to 8 / 4 mm long, projecting backward from the 



