124 American Quarterly Microscopical Jourjial. 



showed that in man there were sometimes two ducts, the larger 

 opening in common with the ductus choledochus, and the 

 smaller independently. Several others of the earlier anatom- 

 ists noted the same fact, but, like Vesling and DeGraaf, con- 

 sidered the presence of two ducts anomalous. 



Sometime before the year 1752, Vater, a Dutch anatomist, 

 described an enlargement or diverticulum of the ductus chole- 

 dochus in its passage through the duodenal walls, and stated that 

 into this enlargement the duct of the pancreas, described by 

 Wirsung, emptied (34 and 22, 455). This enlargement has been 

 named after its discoverer, the Ampulla of Vater. 



To resume the subject of the pancreatic ducts, it is to San- 

 torini, 1775, that we owe the idea of the normal presence of 



Vater, and the duct of Santorini. When right or left is used, it is the right or 

 left of the cat that is meant. 



1 . Plyorus. 



2. The duct of Santorini passing obliquely through the duodenal walls. 



3. Cut end of the inferior pancreatico-duodenal artery. 



4. Same for the corresponding vein. 



5. The duodenal branch of the duct of Wirsung. 



5. Cut end of the duodenal pancreas, showing triangular section, and the in- 

 testines partly enveloped. 



6. The ampulla of Vater. 



7. The duct of Wirsung opening into the ampulla. 



8. The ductus communis choledochus, also opening into the ampulla. 



9. The duodenal branch of the duct of Wirsung. 



10. The gastrosplenic branch. 



11. Duct from the pancreatic reservoir opening by a large branch into 10, 

 and by a small one into 7. 



12. Pancreatic reservoir covering part of the gall-bladder. 



13. The " impeding flexures " in the cystic duct. 



14. The gall-bladder constricted in the middle, as is also the pancreatic reser- 

 voir, by a firm wide band passing over them. 



15. 15. The cystic lobe of the liver. 



Fig. III. Half natural size, from an adult man (After Bernard). Ventral 

 view. The wall of the duodenum partly removed to show the openings of the 

 ducts, which have been exposed by dissection. 



I. Pylorus. 



2 and 4. Duct of Wirsung. 



3. Duct of Santorini anastomosing freely with the preceding, and opening 

 into the intestine between the aperture of the ampulla of Vater and the pylorus. 



5. Ductus communis choledochus. 



6. Opening of the duct of Santorini at the summit of a papilla. 



7. Opening of the ampulla at the summit of a similar papilla. These open- 

 ings are usually about 10-15 "^n^- ^part. 



