538 H. W. NORRIS AND SALLY P. HUGHES 



over the sympathetic trunk, close to the glossopharyngeal gan- 

 glion. A large trunk ganglion occurs on the right side of the 

 single specimen examined, on the left side it is fused with the 

 root ganglion. In Caecilia the second branchial nerve {X.l) 

 arises from the vagal root ganglion, suggesting that in all the 

 caecilians the root ganglion of the vagus is merely the ganglion 

 of a branchial nerve. 



Waldschmidt states that in Siphonops the vagus ganglion is 

 united with a sympathetic ganglion. Marcus figures in the 

 embryo of Hypogeophis three ganglia in the IX-X complex, dis- 

 tinct from the ganglia of the sympathetic trunk. 



2. The glossopharyngeal or first branchial nerve 



From the posterior end of the glosspharyngeal ganglion a 

 nerve is given off which runs for a short distance posteriorly 

 along the dorsolateral border of the sympathetic trunk, then 

 curving ventrally around the lateral border of the latter and 

 passing posteriorly as far as the level of the thyreoid gland, there 

 divides, one branch going anteriorly medial to the thyreoid and 

 then along the dorsal wall of the pharjnix, ramus pharyngeus IX 

 (fig. 44, IXph.). The second branch divides and sends one 

 division anteriorly dorsal to the thyreoid gland along the border 

 of the first branchial arch, later shifting dorsally to pass through 

 the ceratohyoideus internus muscle, which it innervates, to the 

 ventral wall of the mouth, passing along the inner border of the 

 hyoid cartilage and into the base of the tongue, ramus lingualis 

 IX (r. posttrematicus IX) (fig. 44, IXpst.). 



In Dermophis the trunk of the ninth nerve is throughout dis- 

 tinct from the vagus. In its distribution and branching it is 

 similar to the glossopharjmgeal of Herpele. 



From the ventral border of the ganglion, which in Geotrypetes 

 is formed by a fusion of the glossopharyngeal, trunk vagus and 

 sympathetic ganglia, there are successively given off two bran- 

 chial nerves: 1) glossopharyngeal (fig. 37, IXph., IXpst.); 2) 

 first vagal or second branchial (Xph.). 



