604 ON THE ANATOMY OF ANTECHINOMYS ETC. [May 26, 



a vein from the parietes as well as emit one to the renal vein oi- 

 postcaval as the case may be ; there is thus a rudiment of a supra- 

 renal portal system in these animals, not found in at least many 

 Eutherian Mammals. 



(4) Though the intestinal tract of Marsupials is on the whole 

 simple, there are traces {Didel2)hys, Tricliosurus) of the ansse 

 coli and {Trichosurus) of the colico-duodenal ligament of more 

 differentiated forms. 



(5) A gut suspended upon a continuous mesentery is described 

 for the first time not only in Antechinomys, but in Tamandua ; 

 on the other hand, a number of genera of Carnivora 

 are described and the alleged continuous mesentery in Ursus 

 is shown to be only apparent and due to the reduction of the 

 ligamentum cavoduodenale. The continuous mesentery of Centetes 

 is shown to be not universal in the species and is therefoi-e 

 probably to be looked upon as a reversion. 



(6) To the numerous descriptions and figures of Rodents' 

 alimentary tracts gathered together or published for the first time 

 by Tullberg, a description of the colon and ansie coli of Otomys, 

 Aulacodus, and some other forms is added. The enormously long 

 ansa coli dextra of the latter shows that the spiral found in certain 

 Rodents is not necessarily to be looked uj)on as d\ie to the need 

 for packing away such a long loop. The spiral of Hydrochoerus is 

 shown to be a late development since it does not occur in half- 

 grown examples. The colon of the minute Arvicanthis (with one 

 ansa only, the a. paracaecalis) shows that in this group reduction 

 of size is not necessarily accompanied by entire simplification of 

 the gut. 



(7) The older descriptions of the spiral coil in certain Lemurs, 

 e. g. Nycticehus, are shown to be correct as against more recent 

 statements. Microcebus is shown to possess a simple colon without • 

 ansae. Gcdago (2 spp.) is shown to possess a spiral \i^e JShjcticehus 

 &c. And it is pointed out that all the forms with a specialised 

 gut, i. e. with this spiral, are also specialised in the loss of the 

 elsewhere characteristic carpal vibrissse. 



(8) Some account is given of the alimentary tract of the little 

 known species Theropithecus gelada and S'emnojnthecus onelcdojy/ms 

 and the American Ohrysothrix sciureus. 



(9) The intestinal tract of Ryrax, contrary to some statements, 

 has been shown to possess an ansa joaracaecalis which may perhaps 

 be compared to that of the Perissodactyla, and to possess the 

 ligamentum colico-duodenale of more difterentiated forms. 



(10) As a very general rule the loops of the small intestine 

 are loose folds not in any way fixed. Rarely, however (e. g. 

 Dasypus vellerosus), I have found them to be fixed. 



(11) That the colic loops vary is shown by the instance of 

 Lagosto7nus trichodactyhis, in which each of the three individuals 

 dissected by myself or Tullberg is slightly difierent in the 

 propoi-tions of those loops, and by Hyrax cafensis. 



(12) It has been pointed out that in man the omentum is at 



