No. I.] THE CRANIAL NERVES OF AMPHIBIA. 1 39 



ceeding cephalad for a distance after rounding the auditory 

 capsule, and then finally separates. 



These two branches arising thus from the first root are the 

 lateral line nerves supplying the lateral line sense organs of the 

 body ; (/) soon subdivides. 



Besides these principal branches, a small bundle of fibres 

 separates from the ventral division of the first root while still 

 in the vago-glossopharyngeal complex. It proceeds cephalad 

 in the upper inner part of the IX + X trunk, separating as a 

 twig {8) at 897. It will be again treated in its proper place 

 below. 



The ganglionated portion of this nerve appears to be in the 

 region of its forking, thus forming a part of the inner of the 

 three divisions of the vago-glossopharyngeal ganglionic complex, 

 though sometimes a few scattered ganglion cells are found 

 farther out along its course. 



The remaining branches of the IX + X will now be described 

 in the order in which they separate from the ganglia, beginning 

 with those most caudal. The first branch is the dorsal division 

 of the bundle from the first root (/), as described above. 



The second bmnch (2) is the bundle interposed between the two 

 divisions of the first root. It consists of rather small or medium 

 fibres with a few large ones intermingled ; in other words, it 

 resembles those branches of the Trigeminus and the Hyo- 

 mandibularis, which we have seen to have a general cutaneous 

 distribution. It proceeds cephalad close to the auditory cap- 

 sule to 956, where it turns ecto-dorsad, and is distributed to 

 the skin dorsad and mesad of the caudal extremity of the 

 auditory capsule. It has no connection with lateral sense 

 organs. This branch is evidently the same as the one in the 

 frog, known as the R. cntaneus dorsalis. Thus the statement 

 made in Ecker's Anatomy of the Frog (p. 174), that this branch 

 is the persistent portion of the R. lateralis vagi in the tadpole, 

 is erroneous. The supposition of Stannius and Fiirbringer, 

 there referred to, that it is the homologue of the R. auricularis, 

 is evidently correct — if by this it is meant that the Rr. 

 auricularis and cutaneus dorsalis in the frog are similar 

 branches. If it is meant that this branch is the homologue of 



