THE SALIVARY GLANDS 



393 



Lymphatics. Lymphatics are relatively few and are for the most 

 part confined to the interlobularjsepta. where they form cleft-like spaces 

 which lead to true lymphatic vessels and so on to the lymph nodes of the 



cervical region. 



Nerve Supply. The salivary glands are abundantly supplied with 

 nerves, which are derived from both sympathetic^ arid 



They are distributed to the walls of, the blood-vessels and ducts, and 



to the secreting cells of the__acini. The nerve trunks are found in the 



interlobular connective^ tissue where 



they are supplied with small ganglia 



which are most abundant in the sub- 



maxillary and least numerous in the 



parotid gland. 



The sympathetic fibers 

 vate the blood-vessels proc 



which inner- 

 >ed from the 

 They are 



FIG. 364. NERVE ENDINGS IN A 

 SALIVARY GLAND. 



H, demilune; I, secreting acini; 

 n, nerve fibrils. Highly magnified. 

 (After Retzius, from Rauber.) 



superior cervical ganglion 

 believed to be vasodilator jfibers. The 

 cerebral nerves, which suprply fibers to 

 the gland cells, are the facial and the 

 glossopharyngeal. The parotid gland 

 is supplied by the glossipharyngeal ; 

 the fibers (secretory and vasoconstric- 

 tor) passing by way of the tympanic 



nerve (nerve of Jacobson),pnall superficial petrosal, otic (sympathetic) 

 ganglion, and the auriculatemporal branch of the inferior maxillary 

 division of the trigeminal nerve. The submaxillary and sublingual 

 glands receive their secretory fibers and vasoconstrictor fibers from the 

 trigeminal nerve, by way of Ithe chorda tympani nerve and the submaxil- 

 lary (sympathetic) ganglion. The fibers beyond the otic and submaxil- 

 lary ganglia are believed it be true postganglionic fibers; that is, axons 

 of cell bodies situated in these ganglia. Sensory fibers are said to pass 

 to the ducts. 



Delicate fiber bundles from the mjterjobularjnerve trunks^ enter the 

 lobules ana form a plexus of naked fibrils afyoijti ^ p walla nf j-hp anim^ 

 known as the epilemmal plexus, from which terminal fibrils pierce the 

 basement membrane and as liypolemmal fibers end in contact with and 

 between the. secrating cells. Small lerminal expansions, varicosities, or 

 end knobs are found in the course ol the hypolemmal fibers. 





