THE CHORDA TYMPANI. l6l 



(Vidian) nerves grow out from the seventh nerve, un- 

 doubtedly from the geniculate ganglion, and that as late 

 as the fifth week the chorda had not effected its connec- 

 tion with the lingual nerve. These results are of them- 

 selves quite sufScient to confute such work as that of 

 Penzo ('93), who tries to prove by dissection that the 

 chorda tympani and great superficial petrosal nerves con- 

 tain fibres derived from the trigeminus. 



Lenhossek ('94) found that fibres from the cells of the 

 geniculate ganglion enter the portio intermedia, but that 

 the fibres of the large superficial petrosal are not connected 

 with the geniculate ganglion cells. But this negative 

 result cannot stand in the face of the embryological data 

 of Dixon and the degeneration experiments of Amabilino 

 ('98). The latter a^^thor got a characteristic Nissl degen- 

 eration of the cells of the geniculate ganglion after 

 destruction of the chorda, but no degeneration after resec- 

 tion of the facialis. He demonstrated the degeneration 

 of these fibres peripherally of the lesion and also found 

 that some chorda fibres do not degenerate. It is possibly 

 these ascending fibres which Lenhossek found not to ter- 

 minate in the ganglion. Amabilino's work has been since 

 confirmed by Van Gehuchten {Journal de Neurologic^ 

 i8g8), with, however, the important difference that Van 

 Gehuchten found that section of the facial nerve of the 

 rabbit immediately after its emergence from the Fallopian 

 canal does cause degeneration of a few cells of the genicu- 

 late ganglion, thus showing that the facial nerve receives 

 some communis fibres. 



The most important evidence against this conception of 

 the chorda comes from the clinical side. Compare es- 

 pecially the case cited by Adolf Schmidt ('95), which 

 proves conclusively that sensations of taste are transmitted 



