DIGESTION. 109 



dioxide all results calculated at C. and 760 mm. pressure. The 

 greater part of the carbon dioxide was chemically combined. 



The two kinds of submaxillary secretion just named have not 

 thus far been separately studied in man. The secretion may be 

 excited by a psychological conception, by mastication, and by irri- 

 tating the mucous membrane of the mouth, especially with acid- 

 tasting substances. The submaxillary saliva in man is ordinarily 

 clear, rather thin, a little ropy, and froths easily. Its reaction is 

 alkaline. The specific gravity is 1.002-1.003, and it contains 3.6-4.5 

 p. m. solids. We find as organic constituents mucin, traces of 

 albumin and diastatic enzyme is absent in several species of animals. 

 The inorganic bodies are alkali chlorides, sodium and magnesium 

 phosphates, besides bicarbonates of the alkalies and calcium. 

 OEHL finds 0.036 p. m. potassium sulphocyanide in this saliva. 



The Sublingual Saliva. The secretion of this saliva is also 

 influenced by the cerebral and the sympathetic nervous system. 

 The chord al saliva, which is secreted only to a small extent, 

 contains numerous salivary corpuscles, but is otherwise transparent 

 and very ropy. Its reaction is alkaline and contains, according to 

 HEIDENHAI^, 27.5 p. m. solids (in dogs). 



The sublingual secretion in man has been investigated by OEHL. 

 It was clear, mucilaginous, more alkaline than the submaxillary 

 saliva, and contained mucin, diastatic enzymes, and potassium 

 sulphocyanide. 



Buccal mucus can only be obtained pure from animals by the 

 method of BIDDER and SCHMIDT, which consists in tying the exit 

 to all the large salivary glands and cutting off their secretion from 

 the mouth. The quantity of liquid secreted under these circum- 

 stances (in dogs) was so very small that the investigators named 

 were able to collect only 2 grins, buccal mucus in the course .of 

 twenty-four hours. It is a thick, ropy, sticky liquid containing 

 mucin; it is rich in form -elements, above all in flat epithelium- 

 cells, mucous cells, and salivary corpuscles. The quantity of solids 

 in the buccal mucus of the dog is, according to BIDDER and 

 SCHMIDT, 9.98 p. m. 



Parotid Saliva. The secretion of this saliva is also partly de- 

 pendent on the cerebral nervous system (n. glossopharyngeus) and 

 partly on the sympathetic. The secretion may be excited by 



