1912.] 



Temporal Bone not hitherto Described. 



327 



It is hardly possible at present to speak of the physiological significance of this 

 ganglion. Experiment and careful pathological and clinical observation alone 

 can determine this. There is, however, one very interesting clinical fact which is 

 probably worth consideration in this respect. There is a very common form of 

 deafness, unassociated with middle ear disease, and termed otosclerosis. 

 Among other symptoms of this affection are, a diminution in the secretion of 

 wax in the external meatus, and a diminished sensitiveness of the tympanic 

 membrane and the posterior wall of the meatus. These are the regions 

 supplied by Arnold's nerve which is formed by the union of bundles from the 

 pneumogastric and facial nerves. As the stapedial ganglion is composed of 

 fibres derived from both of these nerves it is very possible that autonomic 

 fibres run from it to the parts mentioned. This would account for the 

 diminished secretion of wax in the cases mentioned above. 



DESCRIPTION OF PLATE 6. 



Fig. 1. — The soft structure of the human middle ear. 



i. incus ; /. facial nerve ; s. stapedius muscle ; g.g. ganglion ; a.p. auricular branch 

 of vagus nerve ; t. nerve of Jacobson. 



Fig. 4. — Section through ganglion showing the nerve cells, x 250 ca. 



