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hind edge of the posterior ring of the nasal capsule; but in one spe- 

 cimen it was a short bar connecting that ring with the dorso-lateral 

 end of the anterior horn of the trabecula. The cartilage is always 

 found, and the nerve here in question always passes downward and 

 mesially lateral to it, in the space between it and the palatine. 

 Having traversed this space the nerve immediately sends a branch 

 downward and mesially ventral to the dorso-lateral portion of the 

 anterior horn of the trabecula, and then backward along the lateral 

 surface of the hypophysial canal, undoubtedly innervating the tissues 

 of that canal. The nerve itself continues forward, lying ventro-mesial 

 to the palatine and ventral to a stout fibrous band that here extends 

 downward and mesially, from the lateral edge of the palatine to the 

 ventral edge of the nasal capsule. It lies at first dorsal to the mem- 

 brane that extends from the lateral edge of the hypophysial plate to 

 the mesial edge of the palatine, and that quite probably represents a 

 part of the side wall of the eye-muscle canal, but soon, and when 

 approximately opposite the anterior end of the velo-quadratus muscle, 

 it pierces that membrane and continues forward ventral to it; where 

 it breaks up into several branches, all of which go to the dorsal sur- 

 face of the mouth cavity. This anterior portion of this ventral nerve 

 is thus a palatine nerve, and it would seem to be the homologue of 

 the ramus palatinus posterior facialis of Amia. It seems much too 

 important a nerve to have been entirely overlooked by Müller, and 

 in that case it must be represented in certain of the rami palatini 

 that that author describes as branches of the lower branch of the 

 trigeminus, given off after that nerve has passed downward through 

 fenestra 1 ; an erroneous course and origin if it applies to this parti- 

 cular nerve. 



The ventral branch of the palatinus trigemini of the adult would 

 seem, from its course and distribution, to be the nerve that v. Kupffer 

 says arises, in embryos, from his third epibranchial ganglion. If it 

 be that nerve, it is evident that the third epibranchial ganglion and 

 its root, found separate in embryos, have fused almost completely 

 with the maxillo-mandibularis ganglion in the adult. The dorsal 

 branch would seem to be, as already stated, the homologue of 

 v. Kupffer's nerve b. If it be that nerve it is evident that 

 v. Kupffer is wrong in assigning it to his ganglion A, and, such 

 being the case, this would leave the ophthalmicus ganglion, his gan- 

 glion A, without any branch running ventral to the opticus; this being 

 in accord with the conditions found in all vertebrates other than the 

 Cyclostomes. Furthermore, if these two palatine nerves of the adult 



