248 E. A. BAUMGARTNER 



Goette considered the left outpouching as a rudimentary one. 

 Later the dorsal duct disappears, thus leaving but one perma- 

 nent pancreatic duct. 



Balfour ('81) and Hertwig ('88) described a dorsal outpouching 

 of the gut wall caudal to the level of the common bile-duct. 



The development of the pancreas in both Urodela and Anura 

 was described by Goeppert ('91). In both he found as Goette 

 had described, one dorsal and two symmetrical ventral out- 

 pouchings. A constriction of the early dorsal outgrowth forms 

 a duct, while folds and ridges developing on the blind end give 

 rise to the glandular tissue. The right and left ventral ducts 

 unite on the right side of the common bile-duct. However, he 

 found two pancreatic ducts opening into the common bile-duct 

 in an adult, also three pancreatic ducts that fused immediately 

 before opening into the common bile-duct. The numerous 

 dorsal ducts which he found in the adult urodeles he explained 

 are of secondary origin. He, too, found only one pancreatic 

 duct persisting in adult Anura. 



Marshall ('93) stated that in the frog the pancreas developed 

 as a pair of hollow outgrowths caudal to the liver. Later the 

 ducts shift and open into the bile-duct instead of, as at first, into 

 the intestine. 



Minot ('93) in his text book of embryology, mentioned that 

 in urodeles the dorsal duct persists, and in Anura only the ven- 

 tral duct. 



Weysse ('95) and Stohr ('95) both agreed with the description 

 of Goette and Goeppert. Stohr was especially interested in the 

 dorsal pancreatic anlage. He did not find a double dorsal 

 pancreas as had v. Kupffer ('92) in one of the ganoids. He 

 believed that the caudal dorsal pancreatic anlage described by 

 V. Kupffer is part of the hindgut. Brachet ('96) reviewed the 

 descriptions of earlier investigators. 



Woit ('97), a student of v. Kupffer, and probably influenced 

 by his views, in his work on the development of the spleen 

 stated that the dorsal pancreas gives rise to the spleen as well 

 as to a part of the adult pancreas in urodeles. He described two 

 persisting ducts in urodeles. 



