PANCREAS OF MAMMALIA. 43 



thorhynchus, in the place of the junction of these ducts near the 

 commencement of the ductus choledochus, manifests its affinity 

 to the Marsupials. In these the pancreas extends as usual from 

 the duodenum to the spleen, behind the stomach ; it is charac- 

 terised by a process sent off at right angles, or nearly so, to the 

 main lobe at or near its left extremity. Small and thin processes 

 branch out into the duodenal mesentery (in a Phalanger); and 

 similar but still more numerous processes, in the peritoneal 

 attaching, or omental, fold to the left, give the organ a dendritic 

 appearance in the Kangaroo ; but the splenic process seems to be 

 constant. The pancreatic duct usually opens into the glandular 

 dilatation of the ductus choledochus, and the secretions enter the 

 intestine further from the pylorus than usual. 



The same low type of gland prevails in the Rodentia, and is 

 well shown by Hyde Salter in the rat (Mus decumanus, fig. 380, 

 the main part of the gland being that which extends from the 

 end of the duodenal fold to the left into the gastrosplenic omentum, 

 o, where it ramifies : the chief part of the duodenal pancreas 

 follows the curve of the gut, but ramifies in its wide messentery, 

 d. In the Cavy, where the duodenal loop is longer and narrower 

 than in the Rat, the included portion of pancreas reminds one of 

 the disposition of that in the Bird. In the Capybara the resem- 

 blance is less because the duodenum is shorter, and the corre- 

 sponding part of the pancreas is small : the transverse and larger 

 part of the gland is also more compact than in most Rodents. In 

 the Porcupine the duct of the larger part of the pancreas enters 

 the duodenum far from the pylorus. In the Beaver the pancreas 

 is of considerable extent, measuring in length nearly 2 feet, and 

 following the course of the duodenum down to the iliac region 

 and up again as far as the umbilical, being attached to the intes- 

 tine by a process of mesentery : it is thin and narrow, and has 

 one small branch or process lying parallel with its body where it 

 passes behind the liver, and a few others at the curvature of the 

 duodenum. Its duct, somewhat larger than a crow-quill, enters 

 the small intestine at the extremity of the gland, 1 foot and 

 9 inches from the pylorus, and 1 foot and 6 inches from the ter- 

 mination of the ductus choledochus. 2 This is the extreme of 

 distance from the pylorus and bile-conduits of the entry of the 

 pancreatic secretion into the intestinal tract, which has been ob- 

 served in Mammals : the character prevails in the Rodent order, 

 and Physiologists have availed themselves of it in the Rabbit in 



1 ccxxxi, p. 98. 2 CLXI". p. 19. 



