In a previous paper1 from this laboratory mention was made of the finding of peptic ulcerations of the duodenum just distal to the pylorus in a dog that lost the entire external secretion of the pancreas and was kept alive and in good condition for two weeks with daily intraperitoneal injections of Ringer's solution. This observation was so striking and so unexpected that a number of other dogs were subjected to the same experimental procedure. Duodenal ulcers were found in every case. This finding, as will be pointed out, is not surprising after all and seems to fit in with a number of related observations by others.
Most of the tremendous amount of work that has been done on experimental peptic ulcers has dealt with those on the gastric side of the pylorus. These observations have been successively reviewed by many authors. MacCallum,2 in 1904, reviewed