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the antero-lateral portion of the ganglion the fibers of the facial nerve emerge 
in two parts: an anterior r. palatinus and a lateral r. hyomandibularis. The 
palatine branch passes anteriorly to its anastomosis with the r. ophthalmicus 
profundus already mentioned. A Jacobson’s commissure between the IX nerve 
and the r. pal. VII evidently exists, but its entire course was not traced. The 
main portion of the facial nerve, truncus hyomandibularis, passes posteriorly, 
laterally and ventrally from the ganglion. It soon gives off a r. alveolaris (not 
noticed by Dodds) that passes antero-ventrally to supply the lateral floor of 
the mouth. Its anastomosis with the r. mandibularis V has been described. 
Near the place where the r. alveolaris leaves the hyomandibular trunk the latter 
receives the ramus communicans from the IX nerve. Most of the fibers of the 
r. communicans enter the r. alveolaris and are evidently communis. 
Of the exact composition of the r. communicans no reliable information was 
gained, but apparently general cutaneous fibers are contained in it. The con- 
dition seems to be very much like that described by Coghill in Amblystoma. 
After giving off the r. alveolaris the hyomandibular trunk supplies the depressor 
mandibulae, sphincter colli and interhyoideus muscles and apparently sends 
general cutaneous fibers to the skin overlying these muscles. 
A comparison of a plotting of the fifth and seventh cranial nerves of an adult 
Plethodon with that of a larval Spelerpes (as given by Miss Bowers), shows 
that after omitting the lateral line system of the latter the resemblances are 
very close, so close as to make evident an almost identical arrangement in the 
two. 
It would appear that Dodds is completely in error in supposing that there 
are any anomalies in the composition and distribution of the fifth cranial nerve 
in Plethodon gliitinosus. 
LITERATURE CITED. 
Bowers, Mary a. 
1900. The peripheral distribution of the cranial nerves of Spelerpes bilineatus. Proc. 
Amer. Acad. Arts and Sci., vol. 36. 
Coghill., G'. E. 
1902. The cranial nerves of Amlystoma tigrinum. Jour. Comp. Neurol., vol. 12. 
Dodds, G. S. 
1906. The cranial nerves of one of the salamanders (Plethedon glutinosus). Univ. 
of Colorado Studies, vol. 3, no. 2. 
Norris, H. W. 
1908. The cranial nerves of Amphiuma means. Jour. Comp. Neurol, and Pscyh., 
vol. 18, no. 6. 
