PAKCREATIC JUICE. 331 



duodenum ; 1 one which opens in common with the ductus 

 communis choledicus, and one which opens about an inch 

 above the main duct, called by Bernard the recurrent or ac- 

 cessory duct. The main duct is about an eighth of an inch 

 in diameter, and extends along the body of the gland, be- 

 coming larger as it approaches the opening. The second 

 duct is smaller, and becomes diminished in calibre as it nears 

 the duodenum. Many anatomists describe but a single duct, 

 regarding the other as anomalous. The dissections of Ber- 

 nard, however, were very numerous, and show the almost 

 constant occurrence of two ducts. 2 



In general appearance and minute structure, the pancreas 

 is like the parotid and submaxillary glands. By the older 

 anatomists it was known as the " abdominal salivary gland," 

 on account of this resemblance in structure and an assumed 

 similarity in the nature of their secretions. Recent develop- 

 ments in the physiology of the pancreatic juice have caused 

 this name to be discarded. 



It is only since it has been established by Bernard that 

 one of the most important of the properties of the pancreatic 

 juice is its power of emulsifying liquid fats, that the experi- 

 ments of the older physiologists on the pancreas have assumed 

 any great interest. In the elaborate work of Longet, 3 is 

 a long quotation from Regnerus de Graaf, showing that this 

 physiologist collected fluid from the pancreas in a living dog, 

 in 1662. Following De Graaf, there were others who adopt- 



1 BERNARD, Memoirs sur le Pancreas, Paris, 1856, p. 9. The fact of the al- 

 most constant existence of two pancreatic ducts in the human subject is now 

 recognized by several anatomists. Sappey, out of sixteen dissections of the hu- 

 man pancreas, found, in one instance, a supplementary duct which had no com- 

 munication with the duodenum, so that it was really in this case but a branch of 

 the main duct. In all other instances, there were two ducts, as described by 

 Bernard. ( Traite tf Anatomic Descriptive, Paris, 1857, tome iii., p. 248.) 



2 In dogs and in many other animals, two ducts exist ; so that both must be 

 ligated when it is desired to shut off the pancreatic secretion from the intestine. 



3 LONGET, Traite de Physiologic, Paris, 1861, tome i., p. 256. 



