1895.] AND AMPXJLLARX CANALS OF CHIMiERA. 883 



3. The ramus luccalis passes over the ventral border of the orbit, 

 and, anterior and slightly ventral to it, anastomoses with the ramus 

 maxillaris superior. (PI. Lll. fig. 7, V. r.b.) 



4. The ramus maxillaris passes slightly beneath the orbit as the 

 ramus maxillo-mandibularis. It divides into maxillary and mandi- 

 bular branches, and the former again into the ramus maxillaris 

 superior and ramus maxillaris inferior (PL Lll. fig. 7, V. r.mx.s, 

 & V. r.mx.i.) The ramus maxillaris, as previously pointed out, 

 anastomoses with the buccalis, the combined bi-anches innervating 

 the sub-orbital branch and Y-shaped commissure of the main 

 sensory canal of the head, while the ramus maxillaris inferior 

 innervates the maxiUo-mandibular branch. 



5. The ramus mandibularis branches from the ramus maxillo- 

 mandibularis previously mentioned, passing above and anterior to 

 the foramen through which the ramus palatinus of the facial passes. 

 It breaks up into a series of fine branches, which innervate the 

 mandibular division of the maxillo-mandibular branch of the main 

 sensory canal. 



The Facial Group. — "With the exception of the ramus hyoideus, 

 which innervates the jugular canal of Grarman, no branches of the 

 facial enter into the innervation of the sensory canal-system. 

 Before passing into the orbit the facial is joined by a commissure 

 from the trigeminal. (PL LII. fig. 7, V. com.) 



The Qlossoj)haryngeal nerve arises in front of the Vagus group 

 and passes behind the auditory capsule, ventral to which it divides 

 into three branches. The most anterior runs beneath the ramus 

 hyoideus of the facial and divides up into a series of fine branches, 

 the middle branch passes to the hyoidean gill-cleft, and the postei-ior 

 branch skirts the border of the pectoral fin. (PL LII. fig. 7, IX.) 



Gegenbaur (10. p. 518) states that the glossopharyngeal nerve 

 " leaves the cranial cavity in company with the vagus." I cannot 

 corroborate this statement, as it is very distinct from the vagus, 

 and as I have shown (PI. LIII. fig. 8, IX.) leaves the cranial cavity 

 by a separate foramen. To be quite certain of this I have made 

 four independent dissections, all of which agree with the above 

 description. Since these were finished, I find that Hubrecht (11) 

 also comes to a similar conclusion. It seems hardly possible that 

 Gegenbaur could have confounded the branch of the vagus X. hr. 3 

 (PL LII. fig. 7) with the ninth nerve, and yet this latter is so 

 distinct that it is difficult to see how he could have described it as 

 quoted above. 



The Vagus arises by a series of branches (PL LII. fig. 7), all of 

 which more or less merge into one in the vagus ganglion. The 

 only portion innervating the sensory canal-system is the vagi 

 lateralis. 



The vagi lateralis is the largest branch passing from the vagus 

 ganglion, and is formed by the vagi lateralis proper and a commis- 

 sure from the facial (?). Superficially this commissure arises about 

 5 millim. posterior to the roots of the facial. I was unable in the 

 material at my disposal to cut sections so as to definitely settle its 



