1909.] STKUCTURE OF THE LESSER ANTEATER. 689 



dorsal middle line ; and I also have failed to find this duodeno- 

 caval ligament, as I suppose that mentioned by Flower to be. 



Flower has called attention to the fact that this Anteater, like 

 2£yrmecophaga^ possesses a ventral longitudinal fold in the jejunum 

 and ileum, which is a fixed fold and cannot be obliterated by- 

 stretching the walls of the gut. I have examined this structure 

 carefully in Tamandua, and am able to give a rathei- more detailed 

 account of it than was given by Flower. In the duodenum there 

 is some longitudinal corrugation of the walls of the gut. But the 

 continuous ventral " typhlosole " does not commence until about 

 35 inches behind the stomach. In front of this the fold is occa- 

 sionally seen to the extent of about an inch. The fold is not 

 absolutely continuous from its commencement 35 inches below the 

 stomach. There are two slight gaps at first, two or three fourths 

 of an inch wide. Thereafter this typhlosole is quite continuous 

 as a conspicuous raised fold for a distance of 28 inches. There 

 are in this tract occasional and short branches of the fold, and 

 also short subsidiary and parallel folds. The main fold is 

 fairly deep and very conspicuous. Then follows a gap of 

 7 inches, where the internal surface of the intestine is smooth. 

 After this there is a tract of 20 inches where the typhlosole is 

 again visible ; but it is hei-e, except indeed for very short distances, 

 not nearly so well-marked as it is anteriorly, and there are more 

 subsidiary folds and anastomosing branches. The different 

 appearance will be readily gathered from an inspection of text- 

 fig. 219 (p. 690), which represents pieces from diflerent regions of 

 the small intestine. The rest of the ileum, 7 inches in length, 

 has not any ventral typhlosole. It is clear from the descriptions 

 of both Owen * and Forbes t that the arrangement of this 

 typhlosole in Tamandua difiers in detail from that of Myrmeco- 

 phaga. For both of these anatomists write of a continuous fold 

 throughout the ileum which, according to Forbes, occupies 

 15 feet 3 inches out of a total intestinal length (of the small 

 intestine) of 24 feet 10 inches. In front of this are at intervals 

 detached tracts of this typhlosole-like fold. In Tamandua^ on 

 the other hand, the fold is best developed and continuously so in 

 the middle region of the small intestine. 



In writing of the intestinal coil of Mammals % it had escaped 

 my attention that Sir Richard Owen had already referred to the 

 ^' Reptilian " character of the gut of Myrmecophaga, though I 

 duly noted that Sir W. Flower had described the condition of the 

 gut in that Edentate. It is possible that Flower's statement was 

 taken from Owen's paper, to which he referred. Owen wrote of 

 Myrmecophaga^ that "one common duplicature of peritoneum, 

 ■continued from the middle of the back part of the abdomen, and 

 18 inches in extent where it is broadest, at the junction of the 

 ileum with the colon, supports the whole intestinal canal, as in 



* Trans. Z. S. vol. iv. p. 122. f P. Z. S. 1882, p. 290. 



+ P. Z. S. 1908, p. 570 footnote. § Trans. Z. S. iv. p. 121. 



Proc. Zool. Soc— 1909, No. XLYII. 47 



