Green, Chorda Tytnpatii in Selachians. 415 



in the fishes precludes its anastomosis with a Hngual branch 

 of trigeminus, that nerve not being present in the lower 

 vertebrates. 



These homologies were suggested by Herrick in his Me- 

 nidia paper in 1899, where he has discussed the literature in 

 some detail.^ The description of Stannius seemed so fruitful 

 in suggestions that we have examined some other selachians 

 with a view to confirming and extending his observations. 



In Squalus acanthias we find the conditions corresponding 

 to the description of Stannius, quoted above, almost exactly. 

 The foramen through which the hyomandibular root passes out 

 of the cranium is quite long and the swelling which corresponds 

 to the geniculate ganglion lies far out on the root. Stannius 

 found upon microscopical examination that this swelling in 

 selachians contains ganglion cells. From it a large bundle of 

 fibers is given off into the hyomandibular trunk, the same fibers 

 undoubtedly which peripherally compose the r. mandibularis 

 internus. We also confirm Stannius' description of this nerve. 

 It separates from the trunk near the outer edge of the hyoman- 

 dibular cartilage and curves inward and forward along the outer 

 face of the hyoid arch under the mucosa of the mouth to the 

 end of that arch then runs forward to the lining of the mouth 

 over the tip of the mandible. It is apparently purely sensory. 



^ Some of the more important articles which have appeared since that paper 

 are as follows . 



Dixon, A. F. The Sensory Distribution of the Facial Nerve in Man. 

 Trans. Roy. Soc. of Medicine in Ireland, Vol. XVII, Dublin, 1899, pp. 613-641. 

 K\%o\r\ Journ. Anat. and Physiol., Apr., 1S99. With critical examination of 

 the literature. 



DixoN, A. F. The course of the Taste Fibers. Edinburgh Med.Journ., 

 Apr. and June, 1807. 



Gehuchten, a. van. Recherches sur la terminaison centrale des nerfs 

 sensibles peiiplieriques. I. Le nerf intermediaire de Wrisberg. Le Nivraxe, 

 I, I, 190 .. 



Maximow, A'-.ex. Die Veranderungen der Speicheldriisen nach Durch- 

 trennung der Chorda tympani. Vorllufige Mitt. Centralblatt f. Physiol., 

 XIV, 10, T900. 



KiESOW, F. und Nadoleczny, M. Zur Psychophysiologic der Chorda 

 tympani. Zeits.f. Psycholof[ie,^yilll, i-2, 1900; abstract in Cent. f. Physiol., 

 XIV, 16, p. 430. 



