DIGESTION 



333 



fibres break up into fibrils around nerve-cells situated there and lose 

 their medulla in doing so. A few fibres terminate in a similar manner 

 before entering the hilus. and a few deeper in the gland. The nervous 

 path is continued by the axis-cylinder processes (p. 662) of these nerve- 

 cells, which, passing in as non-medullated fibres, end in a plexus on 

 the basement membrane of the alveoli. From the plexus fibrils run 

 in among the gland-cells, but do not seem to penetrate them. The 

 lingual, the chorda tympani proper, and Wharton's duct form the 

 sides of what is called the chordo-lingual triangle. Within this 

 triangle are situated many ganglion cells, a special accumulation of 

 which has received the name of the submaxillary ganglion. This, 

 however, should rather be called the sublingual ganglion, since its 

 cells, as well as the others in the chordo-lingual triangle, are the 

 cells of origin of axis-cylinder processes, which proceed as non- 



- SM and SL, submaxillary 

 and sublingual glands ; P, 

 parotid ; V, fifth nerve ; VII, 

 facial ; GP, glosso-pharyn- 

 geal ; L, lingual ; CT, 

 chorda tympani ; CL, 

 chordo-lingual ; D, submax- 

 illary (Wharton's) duct ; C, 

 ganglion cell of so-called 

 submaxillary ganglion in 

 the chordo-lingual triangle, 

 connected with a nerve fibre 

 going to sublingual gland ; 

 C", ganglion cell in hilus of 

 submaxillary gland ; SSP, 

 small superficial petrosal 

 branch of the facial ; OG.otic 

 ganglion ; IM, inferior 

 maxillary division of fifth 

 nerve ; AT, auriculo-tpm- 

 poral branch of fifth ; JN, 

 Jacobson's nerve ; C gang- 

 lion cells in superior cer- 

 vical ganglion (SG) con- 

 nected with sympathetic 

 fibres going to parotid, sub- 

 maxillary and sublingual 

 glands. The figure is 

 schematic. 



FIG. 107. NERVES OF THE SALIVARY GLANDS. 



medullated fibres to the sublingual gland. The sublingual gland 

 receives its cerebral fibres partly from branches given off from the 

 lingual in the chordo-lingual triangle after the chorda tympani proper 

 has separated from it, and ending around the nerve-cells within that 

 triangle, partly from the chorda itself in the terminal portion of its 

 course. These statements rest on anatomical and physiological 

 evidence. The latter we shall return to. 



The cerebral fibres for the parotid (in the dog) pass from the 

 tympanic branch of the glosso-pharyngeal (Jacobson's nerve) through 

 connecting filaments to the small superficial petrosal branch of the. 

 facial, with this nerve to the otic ganglion, and thence by the 

 auriculo temporal branch of the fifth to the gland. 



The sympathetic fibres for all the salivary glands appear to arise 

 from nerve cells in the upper dorsal portion of the spinal cord. 



