V.] SUMMARY OF THE FAUNA. 189 



Hystricidae ; in this family the Hystricina are practically 

 restricted to Eastern Arctogaea, although a Javan 

 species is found in Timor. 



UNGULATA. 



Hippopotamidce. E. O.f H.f M.f 



Suidce. H. O. E. M., also extending into the Austro- 

 Malayan region. 



* Anoplotheriida. H. 



* Dichodontidce. H. 



Camelidae ; in this group the genus Camelus, H. E. O., is 



peculiar to Eastern Arctogaea. 

 Tragulidae ; the existing genera Tragulus, O., and Dorca- 



therium, E. H.t, as well as several extinct ones, 



are restricted to this area. 

 Giraffida. E. O.f H.f 

 Bovidae; the whole of the true antelopes and goats, as 



well as most of the sheep and oxen, are restricted to 



Eastern Arctogaea, North America now preserving 



only one species of Bos, Ovis, Ovibos, and Haplo- 



ceros. 



* Palaeotheriidae ; Palceotherium. 



* Lophiodontidae ; Lophiodon. 

 Procaviida. E. H. 



* Dinotheriida. H. O. 



EFFODIENTIA. 



Manida. E. O. H.f 

 Orycteropodida. E. H.f 



To these may be added the absence of living opossums (Didel- 

 phyida}. It will be observed that in this list such existing families 

 as are confined to one of the regions of the area considered are 

 for the most part omitted. Tertiary families which are at present 

 unknown beyond the Eastern Holarctic region have, however, been 

 included, since the limitation is probably in great part due to our 

 want of knowledge of the early Tertiary faunas of the other 

 regions. 



Although the differences indicated between the faunas of 



