THE REGULATION OF SALIVARY SECRETION. 177 



which through previous operation the salivary ducts have 

 been turned outward in such a way that they pour their 

 secretions upon the skin where they may be collected and 

 studied. Not only do such measures bring with them a 

 great saving of animals, but they constitute the only means 

 by which we can obtain a true conception of the normal 

 activity of the gland. How revolutionary are the results 

 obtained by such experimental means which to all intents 

 and purposes leave the laboratory animals uninjured, not 

 only in the case of the salivary glands but all the digestive 

 glands, will be readily apparent from the pages that follow. 

 We will describe first of all GLINNSKI and PAWLOW'S* 

 method of making a permanent salivary fistula. A dog is ordi- 

 narily used. If the parotid saliva is to be collected a small 

 sound is introduced into STENSON'S duct and under chloroform 

 anesthesia a circular incision is made through the mucous 

 membrane around the orifice of the duct. The duct is care- 

 fully dissected free from its surrounding tissues and a hole is 

 punched through the cheek by means of a sharp knife. The 

 duct is drawn through this hole and the collar of mucous 

 membrane is sewed into the edges of the hole. After healing 

 is complete the parotid discharges its secretion upon the 

 cheek. For a study of the secretions of the submaxillary and 

 sublingual glands a similar procedure is followed, but since 

 it is not an easy matter to separate the ducts of WHARTON 

 and of BARTHOLIN the two are usually together sewed into the 

 edges of the external wound. After everything is healed the 

 secretions from the two glands can be separated by a sec- 

 ondary operation in which the ducts are ligatured and opened 

 on the side nearest the gland. In order to collect the saliva 

 which flows from the glands small flanged glass funnels are 

 pasted over the openings by means of a laboratory paste, and 

 from the points of these funnels small graduated tubes are 

 suspended. A dog which has had one or two glands operated 



and PAWLOW: Ergebnisse der Physiologic, 1902, I, Ite 

 Abth., p. 252. 



