ORYCTEROPODID.E 211 



not show the slightest tendency to an approximation towards the 

 Old World forms, we are furnished with an additional reason for 

 insisting on the radical distinctness of the latter, whose phytogeny 

 must therefore for the present remain one of the many unsolved 

 zoological problems." 



The Aard -Yarks (Earth-Pigs) as these creatures are commonly 

 termed, from the name bestowed on them by the Dutch Boers of 

 the Cape, are of nocturnal habits, sleeping during the day in their 

 burrows, which are usually found in the neighbourhood of the tall 

 hills or mounds made by termites. Indeed, wherever these hills are 

 abundant it is stated there is a good chance of finding an Aard-Vark, 

 the food of these animals consisting almost exclusively of termites 

 and ants. 



Tavo existing species are recognised, namely the Cape Aard-Vark 

 (0. afra) from South Africa, and another (0. cethiopicus) from the 

 north-eastern parts of Africa, ranging into Egypt. An extinct 

 species has been described from the Lower Pliocene of the Isle 

 of Samos, in the Turkish Archipelago, differing from the exist- 

 ing forms by the larger proportionate size of the lateral meta- 

 tarsals. 



Bibliography of Edentata. — No general work on the order has been published 

 since that of Rapp (Anat. Untcrsuchungen iiber die Edcntatcn, 2d ed. 1852). 

 Among numerous memoirs on special groups the following may be cited : — 

 Myrmecophagidce : — R. Owen, "Anatomy of Great Anteater," Trans. Zool. Soc. 

 vol. iv. ; G. Pouchet, Mem. sur le Grand Fourmilicr, 1874 ; W. A. Forbes, 

 "Anat. of Great Anteater," Proc. Zool. Soc. 1882, p. 287. Megatheriidce .-— R. 

 Owen, Extinct Gigantic Sloth {Mylodon Robustus), 1842; Id., "On the Mega- 

 therium," Phil. Trans. 1851-56; J. Leidy, "Extinct Sloth -tribe of North 

 America," Smithsonian Contrib. to Knowledge, vii. 1855 ; H. Burmeister, 

 Description de la Republique Argentine, t. iii. Mammiferes, 1879,— which contains 

 full references to various memoirs by Owen, Gervais, Reinhardt, and others. 

 Hhiptodontidoz :— Owen, Catalogue of Fossil Mammals, Mus. Roy. Coll. Surgeons, 

 1845 ; T. H. Huxley, "Osteol. of Glyptodon, " Phil. Trans. 1865 ; H. Burmeister, 

 Annales del Museo Publico de Buenos Aires, and Dcscript. de la Republique 

 Argentine, 1879 ; H. Gervais and F. Ameghino, Les Mammiferes Fossiles de 

 VAmirique Meridionale, Paris, 1880,— which also contains a list of all the 

 S. American Edentates described at that date. Dasyp>odidce : — J. Murie, "Ana- 

 tomy of Tolypeutcs" Trans. Linn. Soc. vol. xxx. 1874 ; A. H. Garrod, Proc. 

 Zool. Soc. 1878. For Placentation of Edentates see W. Turner, Trans. Roy. Soc. 

 Edin. xxvii. (1873) p. 72, and Journ. Anat. and Physiol, vols. viii. and x. ; A. 

 Milne-Edwards, Ann. Sciences Nat. [6] viii. p. 1 ; and for brain, P. Gervais, 

 "Formes cerebrales des Edentes," Nouv. Arch, du Musi urn, torn. v. ; W. Turner, 

 Jour. Anatomy, i. 313 (1867). For the dentition of Orycteropus see 0. Thomas, 

 "A Milk Dentition in Orycteropus," Proc. Roy. Soc. vol. xlvii. p. 246 (1890). 

 Fuller observations on the mutual relations of the various families are given by 

 W. H. Flower, " On the Mutual Affinities of the Animals composing the Order 

 Edentata," Proc. Zool. Soc. 1882, p. 358. 



