IXTESTIXAL TRACT OF MAMMALS. 



239 



but foi'ming an ansa colt sinistra. Dr. Beddai-d does not refer to 

 this in the case of Chiromys, although it is indicated in his 

 figure (Beddard, 1908, p. 150), but this omission is no doubt due 

 to the fact that he does not recognise a loop as a distinct entity 

 uidess it has attained a certain degree of definiteness, and 

 especially when it is " fixed " by some ligament other than its 

 primitive mesentery. I apprehend that the expansion of the region 

 of the hind-gut, just distad of the summit of the pendant loop in 



Text-fio'ure 30. 



Intestinal tract of Lemur ? species. 

 Lettering as in text-fio-. 29. 



my figure of Chirogaleus (Mitchell, 1905, fig. 40), represents in a 

 still less defined condition the ansa coli sinistra, and is not 

 identical with the ansa coli dextra marked C.L. in figure 39 of 

 the same communication. Burraeister's figure of the intestinal 

 tract of Tarsius (Burmeistei', 1846) is not easy to interpi'et, as 

 the gut has been freed from the mesentery, but it seems probable 

 that there is no ti'ace of an ansa coli de.vtra or sinistra but a 

 rather wide sweep I'epresenting a transverse colon. A figure 

 given by Klaatsch (Klaatsch, 1892, pi. xxiii. fig. 8) confirms this 

 interpretation. The rectal portion of the hind-gut in Prosimite 

 runs a straight course to the anus, distad of the ansa coli sinistra, 

 if that be present. 



As Dr. Beddard has described, there are several secondary 

 connections or ligaments in the intestinal tract of Prosimije. 



