CHAP. I.] PAROTID SALIVA. 25 



it sometimes, however, contains mucin. According to Kiihne there is 

 evidence that the proteids consist of a globulin-like body, of an 

 alkaline albuminate and albumin 1 . 



The parotid saliva of the lower animals usually gives with ferric 

 chloride a white precipitate containing proteids ; that of man on the 

 other hand usually displays the sulphocyanide reaction. 



Parotid saliva when exposed to the air either deposits a slight 

 sediment of calcium carbonate, or becomes covered with a pellicle 

 consisting of amorphous or crystalline calcium carbonate. 



composition Stimulation of Jacobson's nerve (tympanic branch 

 of parotid sa- of glossopharyngeal) as already stated at p. 22, occa- 

 sions a flow of watery saliva rich in salts and poor in 

 of sympathetic P r teids. In the majority of cases stimulation of the 

 and giosso- sympathetic fibres going to the parotid in the dog does 

 pharyngeal not produce any flow of saliva ; if, however, this stimu- 

 contrasted. lation be superadded to that of Jacobson's nerve, there 

 is a marked increase in the amount of solid matter and especially of 

 the organic solid matter excreted 2 . This statement rests upon such 

 observations as those of which the results are subjoined. 



COMPOSITION OF PAROTID SALIVA OBTAINED BY STIMULATION OF 

 JACOBSON'S NERVE WITH AND WITHOUT SIMULTANEOUS STIMULA- 

 TION OF THE SYMPATHETIC. (HEIDENHAIN 3 .) 



In 100 parts. 

 Total q ,, Organic 

 solids. lts< solids. 



1. Stimulation of Jacobson's nerve without] A K /j A 01 



,. i ,. ,. ,1 ,. > U'OO U'Ol U'Ji 



stimulation of sympathetic j 



2. with 2-42 0-36 2-06 



3. vnthout 1-03 0-26 0-76 



4. with 1-74 0-32 1-41 



5. without 0-57 0-36 0-21 



6. with 0-64 0-25 0-38 



7. without 0-49 0-32 0-16 



3. SUBMAXILLARY SALIVA. 



Introductory Observations. 



The submaxillary gland in most animals is typically a mucous 

 gland, and its secretion is characterized by viscidity due to the 

 presence of mucin. 



The submaxillary gland is relatively more highly developed in 

 carnivorous than herbivorous animals. Claude Bernard sought to 

 establish the specially close connection between the submaxillary 



1 Kiihne, Lehrbuch, p. 14. 



- Heidenhain, ' Morphologische Veranderungen der Driisen wahrend der Thatig- 

 keit,' Hermann's Handbuch, Vol. v. (1880), Part i. p. 61. 



3 Heidenhain, ' Beziehungen der Halssympathicus zur Parotis beim Hunde.' 

 Hermann's Handbuch, Vol. v. pp. 54 and 55. 



