Terminal distribution of the branch termed Ramus communicans cum nervo glossopharyngeo of the facial nerve and its morphological significance.

It has already been clarified that the branch termed Ramus communicans cum nervo glossopharyngeo of the facial nerve in the current Nomina anatomica was in fact one of the branches of the glossopharyngeal nerve that ran towards the auricle [Kawai et al., 1989]. For this investigation, using 5 head sides including 3 with this branch, the author studied the course and the terminal distribution of this branch and compared the data with those of the usual vagal auricular branch which is known to be distributed into the auricle. As a result, the author confirmed that the branch in question was distributed into the cutaneous layer of the concha of the auricle and the posterior wall of the external acoustic meatus, into which the vagal auricular branch is usually distributed, and that the usual vagal or glossopharyngeal auricular branch existed simultaneously with the branch in question in 3 cases. These results suggest that this branch of the glossopharyngeal nerve does not appear simply as a compensatory branch in place of the usual vagal auricular branch.