NERV'ES IN THE MEMBRANA TYMPANT OF MAN 111 



tute such a serial chain" (p. 84). As the "ganglion of the audi- 

 tory nerve may be primarily involved in zona" (p. 340), and so 

 would be embraced within this series, it only remains to explain 

 the implication of the facial from inflammatory changes in the 

 geniculate. 



I recognize the cogency of Hunt's arguments but feel that some- 

 thing further is required to elucidate the point in question. There 

 are two obvious possibilities, namely, that the fibers which I have 

 shown reach the external auditory meatus by the n. auriculo- 

 temporalis may come from the geniculate through the n. petrosus 

 superficialis minor and the further possibility that fibers may pass 

 from the n. facialis to the auricular branch of the n. vagus and 

 so reach the meatus. In order to arrive at a conclusion in this 

 possible peripheral distribution I have recently deslroyed the 

 geniculate in dogs and monkeys so as not to involve the ninth or 

 tenth cranial nerves nor the branches from the second and third 

 cervical. When the series are completed I hope to publish the 

 results. 



CONCLUSIONS 



The membrana tympani of man is chiefly supplied by nerves 

 which enter from the external auditory meatus. These pass in 

 (1) as one large trunk along with the principal artery; (2) as 

 numerous small branches around the periphery. 



These form a plexus in the fibrous tissue from which branches 

 are distributed to a sub-epithelial and a sub-mucous plexus. In 

 addition there are to be distinguished a zonular and an intra-epi- 

 thelial plexus. 



There are nerves, fewer in number, which enter from the tym- 

 panic cavity. 



The blood vessels are well supplied by vaso-motor nerves. 



Only one variety of nerve ending is seen in the epithelium. In 

 the fibrous tissue both subcutaneous and submucous there are 

 found nerve arborisations; at the periphery modified vater-pac- 

 inian corpuscles are present. 



No ganglia are to be seen. 



