330 SOLID PARTS OF ANIMALS. 



Berzelius concludes from these experiments, that the capillary 

 tubes of the kidneys contain a liquid very rich in albumen, and 

 rendered acid by the presence of a little lactic acid. But that 

 no fibrin exists in it. Berzelius attempted in vain to discover 

 the presence of urea in the liquid from the kidneys.* But the 

 presence of that substance has since been detected in it. 



CHAPTER XXVI. 



OF THE OTHER GLANDS. 



BESIDES the mammae, pancreas, liver, and kidneys, there are 

 many other glands in the living body, destined to secret various 

 substances for purposes connected with the welfare of the living 

 animal or with the continuance of the species. It may be proper 

 to notice some of the most important of these glands in the pre- 

 sent chapter. 



1. Salivary glands. These glands are six in number ; name- 

 ly, two parotid, two submaxillary, and two sublingual ; one of 

 each on each side of the face. 



The parotid gland, as the name implies, is placed near the ear. 

 It extends from the zygoma to the angle of the jaw and the mas- 

 toid process. It has a pale-ash colour, and is composed of mi- 

 nute granules aggregated into lobules and lobes. The external 

 surface of the gland is covered by the skin and partially by the 

 platisma muscle, and bound down by a prolongation of the cer- 

 vical fascia. The external carotid artery and vein passes through 

 its substance, and also the fascial nerve. The chemical proper- 

 ties of this gland have not hitherto been subjected to examination. 

 Nor does it seem possible to separate the glandular tissue from 

 the numerous vessels with which it is filled. 



The submaxillary gland lies behind and beneath the ramus of 

 the jaw. It is separated from the parotid gland by the stylo- 

 maxillary membrane, where it is covered by the skin and platis- 

 ma, and invested with a thin membrane of cellular tissue. The 

 facial artery runs in a groove on its upper suface. Its excre- 

 tory duct, called ductus Whartoni, terminates towards the side of 



* Traite de Chimie, vii. 334. 



