1882.] PROF. W. H. FLOWER ON THE EDENTATA. 3C>3 



eaters are closely similar in structure, while those of Manis are formed 

 upon a totally different type. In the former families the testes are 

 placed exactly in the same situation, close to each other, lying on the 

 rectum, between it and the bladder ; the penis is quite rudimentary, 

 consisting of a pair of small corpora cavernosa, not directly attached 

 by their crura to the rami of the ischium, and having a glans scarcely 

 larger than that of the clitoris of most mammals, and, as in birds and 

 reptiles, without any true corpus spongiosum. Tlie number and 

 development of the accessory glands vary apparently in different 

 species of both families. 



In the females of both Anteaters and Sloths the uterus is simple 

 and globular, and the vagina, at least in the virgin state, is divided 

 into two channels by a strong median partition. Lastly, the placen- 

 tation, as far as it is known, if not identical, is similar in principle. 

 The placenta of Choloepus has been fully described by Turner ; it is 

 deciduate, and composed of a number of lobes aggregated into a 

 dome-like mass. There is nothing in the descriptions, certainly less 

 complete, of the placenta of Tamandua and Cycloturus to show any 

 differences except in detail of form. 



In Manis, on the other hand, the testes are totally different in 

 position, lying in the inguinal canal. The penis is external and 

 well developed. The uterus is truly bicornuate, the vagina not 

 divided, and the placenta diffused and non-deciduate. All the 

 organs and foetal membranes are formed very much on the plan of 

 those of the typical Uugulata, without a trace of the special peculi- 

 arities of the American Edentates. 



As regards the tegumentary system Myrmecophaga closely re- 

 sembles Bradypus in the character of its hairy covering ; while 

 Manis, in its very remarkable horny scales, shows a type entirely 

 different from both and from every other mammal. 



INIany other minor considerations might be adduced ; but I think 

 I have brought forward enough to establish the fact beyond reason- 

 able question, that Manis, if allied at all to Myrmecophaga, 

 must have separated from the original common stock before this 

 had given off the Bradypodidce — or, in other words, that the Sloths 

 and Anteaters, with the Megatherioids intervening, are far more 

 nearly allied to each other than either is to the Pangolins. 



It now remains to examine the position of the other families. 



Dasypodidce. In many respects this family is remarkably specia- 

 lized, more particularly in the characters of the integumentary 

 structures, in which it differs from all known mammals. 



In dental characters it presents nothing fundamentally different 

 from those of the Sloths. In lingual, salivary, and digestive organs, 

 on the other hand, it is more nearly allied to the Anteaters, though 

 presenting a less extreme form of modification, showing in fact one of 

 the stages by which such modification may have been brought about. 

 It is therefore so far a connecting link between these families. 



In the extremely important character of the presence of inter- 

 locking accessory zygapophyses to the lumbar vertebrse, and in the 

 structure of the sternum and sternal ribs, it follows the type of Myr- 



