THE PANCREAS 269 



but, as the cyst is only covered by the muscular abdominal 

 wall, careful palpation may determine that it is separate from 

 the liver. In most cases, the cyst reaches the anterior 

 abdominal wall below the greater curvature of the stomach, 

 pushing the gastro-colic ligament in front of it. Percussion 

 reveals the presence of a dull area which intervenes between 

 the tympanitic stomach note above and the tympanitic note 

 of the transverse colon below. 



The main duct of the pancreas begins in the tail of the 

 gland and passes to the right ; after traversing the body and 

 head of the pancreas the duct pierces the duodenal wall and 

 opens into the ampulla of Vater (p. 263). Near its termina- 

 tion it may be obstructed by tumours of the head of the 

 gland or by a calculus impacted in the ampulla of Vater. 

 The latter condition is of two-fold interest. In the first 

 place, it may be the forerunner or exciting cause of pancreatitis, 

 as the bile may flow backwards along the pancreatic duct and 

 damage the gland tissue. In the second place, obstruction 

 to the outflow from the main pancreatic duct may be com- 

 pensated for by the dilatation of a connexion which some- 

 times exists between the main duct of the pancreas and an 

 accessory duct. The latter is confined to the head of the gland 

 and it opens into the duodenum by a separate orifice, placed 

 a short distance above the ampulla of Vater (Fig. 98). 



The Lymph Vessels of the pancreas terminate in the cceliac 

 glands (p. 249), after passing through the subpyloric, pancreatic 

 and other subsidiary groups. The occurrence of secondary 

 deposits in the pancreas following primary cancer of the 

 stomach has already been mentioned. 



DEVELOPMENT OF THE PANCREAS. The presence of two 

 pancreatic ducts, both opening into the duodenum, is explained 

 on reference to the developmental history of the gland. Shortly 

 after the appearance of the diverticulum which forms the liver 

 (p. 264), two similar diverticula grow out from the ventral 

 surface of the duodenum, and one of these normally disappears. 

 The other, which is situated at the point where the liver 



