666 PHYSIOLOGY 



The fibres are apparently finally distributed to the secreting alveoli, 

 where they end freely on the secreting cells just below the basement mem- 

 brane. They do not, however, take an uninterrupted course. By means 

 of the nicotine method Langley has shown that all the fibres to the sub-lingual 

 and the sub-maxillary glands end somewhere near the glands in connection 

 with ganglion-cells. From the ganglion-cells fresh relays of fibres are given 

 off which pass to the gland-cells themselves. The fibres going to the 

 sub-maxillary gland are connected with scattered cells lying in the substance 

 of the gland itself ; in the cat those passing to the retro-lingual gland are 

 connected for the most part with the ganglion-cells which make up the 



ylohyoid 



ngual. N 



Hyogflossus 

 Genibhyoid 



FIG. 324. Diagram of the arrangement of the nerve-supply to the sub-maxillary 



gland, as exposed in an actual experiment. 



Duct,Wh, Wharton's duct (of sub-maxillary) ; Duct.R.L, retro-lingual 

 duct ; Ch.Ty, chorda tympani nerves. (ALCOCK and ELLISON.) 



so-called ' sub-maxillary ganglion.' The fibres to the sub-lingual gland in 

 man probably take a similar course. 



The fibres to the parotid gland pass along the glossopharyngeal nerve 

 and its tympanic branch (nerve of Jacobson) to the tympanic plexus. Hence 

 the fibres are carried by the small superficial petrosal nerve to the otic 

 ganglion, and thence by the auriculo- temporal, which is a branch of the 

 third division of the fifth nerve. 



The sympathetic supply to all these glands is contained in fine filaments 

 on the walls of the arteries with which they are supplied. The fibres are 

 derived ultimately from the spinal cord, whence they issue by the upper three 

 anterior dorsal nerve-roots. They pass into the stellate ganglion, round the 

 ansa Vieussenii to the inferior, and so to the superior cervical ganglion 

 of the sympathetic. Here the fibres end around the cells of the ganglion, 

 and a fresh relay of fibres, chiefly non-medullated, arise from the cells and 

 travel on the walls of the branches of the external carotid artery to their 

 destination. 



The effect of stimulating the peripheral ends of the cerebrospinal nerves 

 going to the glands presents a general resemblance, whichever be the gland 

 involved. Within a period of half to two seconds after the stimulation has 

 been applied, a secretion of saliva is produced, presenting similar characters 



