THE SPLEEN IN MARSUPIALS. 



In this order we meet not only with types of spleen 

 presenting the early mammalian character seen in the 

 Monotremes, but with types becoming dorsally fixed and 

 resembling closely the human spleen. 



Tasmanian Devil (Dasyurus sarcophilus). 



In this Marsupial there is a well-defined great 

 omentum extending from the pyloric region to the left 

 along the great curve of the stomach. No duodenal loop 

 is present, and no well marked distinction between colon 

 and small intestine as in other Marsupials. The intestinal 

 tract is reptilian in character, consisting of a canal 157 

 cm. from pylorus to pelvis, swung apparently on a single 

 mesentery 7 cm. long at its dorsal attachment. This latter 

 consists of two portions — an upper 1.5 cm. long (superior 

 mesenteric) and corresponding to the duodenum and 

 small gut (135 cm.), and a lower (5 cm.) representing the 

 original mesocolon and corresponding to the remaining 

 22 cm. of intestine, which is large gut. (Page 94.) 



As in Macropus, the spleen presents three distinct 

 portions : — 



(1) A large portion or body directed along the great 

 curvature of the stomach towards the oesophagus. It is 

 swung on the great omentum, which is 2 cm. wide at the 

 left extremity and 10 cm. at the right. At the left 

 extremity, in addition to the shortened omentum (gastro- 



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