496 



THE SALIVAR Y GLANDS. 



parotid of a rabbit 3 to 6 per cent. In the cat the percentage of 

 organic substance in sympathetic saliva from the submaxillary gland is 

 small (about O5 per cent.), and less than that in the chorda saliva. 



The percentage of salts in sympathetic saliva does not exceed the 

 percentage of the salts in saliva produced by stimulating the cranial 



nerve. 



The analyses of the parotid saliva in the rabbit have been made by 

 Heidenhain. 1 I extract the following from one experiment : 



Parotid Gland Rabbit. 



The sympathetic saliva in the cat 2 is, as I have said, usually less viscid 

 than chorda saliva. But it is possible that a strong or prolonged stimulation 

 of the sympathetic might give rise to a saliva with a higher percentage of 

 solids than the chorda saliva. I append an analysis of sympathetic and chorda 

 saliva in the cat, obtained by moderately strong interrupted currents. 



The sympathetic secretion in the cat is very much like the " augmented " 

 secretion of the gland of the dog (cf. infra), in that it starts quickly, 

 quickly becomes slow, and is watery. It differs in the rapidity of recovery 

 from the effect of immediately preceding sympathetic stimulation. The 

 maximum amount of secretion is obtained by stimulating fifteen seconds out 

 of every thirty, or even for shorter periods. 



In certain circumstances the sympathetic may produce a brief rapid 

 secretion from any or all of the salivary glands. That is the case when 

 it is stimulated shortly after stimulation of the cranial nerve. There is 

 a rush of saliva, quickly following the sympathetic stimulation, reaching 

 its maximum in a few seconds, and, after about seven to ten seconds, 

 rapidly declining. A very brief stimulation of the cranial nerve is 

 sufficient to increase in this way the amount of saliva obtained from 

 the sympathetic. And thus, if the cranial nerve and the sympathetic 

 nerve be stimulated alternately, a not inconsiderable quantity of 



1 Arch.f. d.ges. PhysioL, Bonn, 1878, Bd. xvii. S. 38. 



2 Langley, Journ. PhysioL, Cambridge and London, 1878, vol. i. p. 

 p. 92. 



1885, vol. vi. 



