36 SPECIAL HISTOLOGY. 



the vessels, into the interior of the glands ; in addition, the 

 ganglion linguale (lingualis and chorda tympani) supplies the 

 two smaller pair of glands, and the facial nerve, probably with 

 the anterior auricular, the parotid. I may remark, with regard 

 to the distribution of these numerous nerves, that here also 

 it is impossible to find any in the smallest lobules of the 

 glands, while on the other hand they are readily discovered 

 upon the larger vessels and the excretory ducts. In animals 

 I found particularly rich nervous networks upon Rivini's ducts, 

 the tubules having a diameter of 0-001 — 0002"'. 



The secretion of the salivary glands normally contains no 

 formed elements, but may accidentally present cylindrical cells 

 from the excretory ducts, or scattered, half-disorganised cells 

 from the glandular vesicles. Its physical and chemical pro- 

 perties, in the different salivary glands, appear to differ in some 

 respects. The parotid saliva is clear and fluid, and, like the 

 glandular vesicles themselves, contains no mucus. Bernard and 

 Jacubowitsch found the secretion of the sub-maxillary gland 

 in the Dog to be viscid, and capable of being drawn out into 

 threads ; according to Bernard also, a watery extract of the 

 gland itself contains mucus. 



In man, the ductus WJiartonianus, if laid open, is usually found 

 to contain a small quantity of a kind of mucous fluid, which, 

 however, consists chiefly of cylinder epithelium and broken up 

 epithelial cells of the glandular vesicles themselves, contain- 

 ing only a very small amount of a substance which coagulates 

 in acetic acid, and is, perhaps, mucus. The glandular vesicles, 

 on the other hand, if crushed, usually yield a considerable 

 quantity of mucus, which coagulates into threads by the action 

 of acetic acid. The vesicles of the proper sublingual gland con- 

 tain still more mucus, and the ductus Bartholinianus also com- 

 monly presents distinct evidence of it. With respect to Rivini's 

 ducts, they are filled, in man and animals, with the same 

 yellowish, viscid, amorphous fluid, coagulating into threads by 

 the action of acetic acid, which is met with in the ducts of 

 the small mucous glands, while the glandular vesicles them- 

 selves also contain abundant mucus. From all that has been 

 said, it would seem that Rivini's glands, as I will call them, 

 must be excluded from the class of salivary glands, and, as re- 

 gards the three larger glands, their secretion does not appear to 





