1908.] 



ANTECHIXOMYS ANB OTHER MARSUPIALS. 



565 



indeed so large as to suggest tluit the animal had recently boi-ne 

 young. [N'either were there any signs of immaturity about the 

 organs of reproduction. Nevertheless, there was a large per- 

 sistent urachus or umbilical cord. There is no question here of 

 mere traces or of a minute rudiment of this structure. It was 

 large and conspicuous, as is plainly shown in the accompanying 

 figure (text-fig. 113). Whether this umbilical cord does or does 

 not contain any fvmctional blood-vessels 1 cannot say. All 

 vestiges of blood-vessels were invisible on dissection. More- 

 over, although I have used the term " cord " to express this 

 sti'ucture, it is by no means an exactly descriptive word. When 

 the animal was dissected under water the membrane forming 

 the umbilical cord floated out loosely, being merely gathered 

 together at the point where it perforates the rectus abdominis 

 muscle to be attached to the skin. 



Text-fig. 113. 



"Umbilical cord" and adjacent viscera oi FhascoJogaU macdonellensis. 



int. Intestine. O. Omentum. It. Eectiis muscle perforated by umbilical 

 cord. St. Stomach. 



The attachment of this membrane to the intestine fixes that 

 "tube, as is natural, in a definite position ; if it were not for this 

 persistent umbilical cord the intestine could be, as I imagine, 

 laid out in a continuous cvirve as in Antechinomys. The point 

 where the umbilical membrane is attachecj to the gut represents, 



