PLATYPUS AND ECHIDNA. 



(/>) Two duets opening opposite one another — one 

 from pancreas in the gastro-hepatic omen- 

 tum — one from rest of pancreas. 



(c) Two ducts, but left opens proximal to right. 



(<l) Single duct on left — traced in the gastro-hep. 

 omentum towards the pylorus, then down 

 and to the right in mesoduodenum, and then 

 to left. Total length, 12 cm. 



Pancreas in Echidna. — (1 ) The pancreas is a more 

 compact and less mobile organ than in Platypus, and may 

 be in close relation with the dorsal abdominal wall and 

 the lobus caudatus of the liver, so as to be regarded as a 

 "fixed'' organ. (2) The great omentum is well defined 

 and traced along the great curvature of the stomach, but 

 does not extend as far to the right along the duodenum 

 as in the Platypus. It never extends beyond the pylorus, 

 and may even end at the beginning of that elongated giz- 

 zard-like structure. It has the spleen on its left side, and 

 its length is lb' cm., and width below 12 cm. (3) There 

 is, as in Platypus, a well defined duodenal loop which 

 contains the main portion of the pancreas. Pancreatic 

 tissue may be traced to the left of the duct in the gastro- 

 hepatic omentum above the pylorus, and even reaching to 

 the stomach wall. It is also traced along the duct as far 

 as the portal interval of the liver. The pancreas related 

 to the duodenal loo]> is mobile usually, though the mobil- 

 ity is limited. This portion is usually connected to the 

 lobus caudatus of the liver by a peritoneal band. There 

 is a slight interval between the pancreas and the duodenal 

 wall, as in Platypus. 



(4) The colon comes into relation with the pancreas 

 about the root of the mesentery and duod-intest flexure. 

 Here the pancreas is fixed dorsally in all specimens 

 examined. As in Platypus the body and right process of 



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