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Show 1895.] AND AMPULLARY CANALS OP CHIMERA. 883 3. The ramus buccalis passes over the ventral border of the orbit, and, anterior aud slightly ventral to it, anastomoses with the ramus maxillaris superior. (PI. LIT. fig. 7, V. r.b.) 4. The ramus maxillaris passes slightly beneath the orbit as the ramus maxillo-mandibularis. It divides into maxillary and mandibular branches, and the former again into the ramus maxillaris superior and ramus maxillaris inferior (PI. LII. fig. 7, V. r.mx.s. & V. r.mx.i.) The ramus maxillaris, as previously pointed out, anastomoses with the buccalis, the combined branches innervating the sub-orbital branch and Y-shaped commissure of the main sensory canal of the head, while the ramus maxillaris inferior innervates the maxillo-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 Garman, 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. (PI. LII. fig. 7, V. com.) The Glossopharyngeal 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 posterior branch skirts the border of the pectoral fin. (PI. 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 (PL 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 . br. 3 (PI. 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 commissure from the facial (?). Superficially this commissure arises about 5 millim. posterior to the roots of the facial. I was unable in the material at m y disposal to cut sections so as to definitely settle its |