V.] EFFODIENTIA. l8/ 



American bison not far removed from its Caucasian cousin (Bos 

 bison], so that all these forms are probably descended from 

 ancestors inhabiting Eastern Arctogaea. 



In the perissodactyle section of the ungulates, if we take fossil 

 forms into account, there are no families peculiar to this area; but 

 among extinct forms we have the large Oligocene genus Palceo- 

 therium 1 , and the Eocene Lophiodon absolutely restricted to it. 



Although occurring only in Syria and the Ethiopian region, and 

 at present unknown in a fossil state, the peculiar subordinal group 

 of ungulates represented solely by the hyraces (Procaviidce) per- 

 haps deserves mention among the types characteristic of Eastern 

 Arctogaea. A nearly similar observation applies to the extinct 

 proboscidean family Dinotheriidce, in which the single known 

 genus (Dinotherium) ranges from the Miocene and Pliocene of 

 Europe to the Pliocene of Northern India. 



Of the edentates, with the exception of certain very doubtful 

 forms from the French phosphorites, which may prove to be 

 reptilian, we have no evidence of the existence of any representa- 

 tives in the Old World. There are, however, in Eastern Arcto- 

 g?ea two very peculiar families commonly assigned to the same 

 order as the latter, although it seems preferable to regard them as 

 indicating an ordinal group (Effodientia) by themselves. Of these 

 the pangolins (Manidce), which are distinguished from all other 

 mammals by their covering of overlapping horny scales, are now 

 confined to the Oriental and Ethiopian regions, to which the one 

 living genus Manis is common ; but they appear to have been 

 represented in the Oligocene phosphorites of France by smaller 

 extinct forms, to which the names Necromanis and Leptomanis* 

 have been given. The second family, Orycteropodidce, of which 

 the only living members are the Ethiopian aard-varks (Orycteropus), 

 differ very widely from the last, the body being nearly naked, and 

 the molar teeth characterised by a peculiarly complex structure 

 which is unique in the whole mammalian class. A fossil species 

 of the existing genus has been discovered in the lower Pliocene of 

 Samos and Maraga, in Persia ; while the extinct genus Pal&orycte- 



1 Teeth figured on p. 166. 



2 The so-called Palceomanis, from the Pliocene of Samos, turns out to have 

 been founded on remains of an ungulate. 



