CHAP. XVII.J 



MAMMALIA. 



231 



an extinct genus, Eumys, in the Upper Miocene of Dakota, and 

 another, Myso'ps, in the Eocene of Wyoming. 



In South America Mus, or more probably Hesperomys, is 

 abundant in Brazilian caverns, and Oxymyderus in the Pliocene 

 of La Plata ; while Arvicola is said to have occurred both in the 

 Pliocene and Eocene deposits of the same country. 



Family 56.— SPALACID^. (7 Genera, 17 Species.) 



The Spalacidse, or mole-rats, have a straggling distribution over 

 the Old World continents. They are found over nearly the whole 

 of Africa, but only in the South-east of Europe, and West of 

 Temperate Asia, but appearing again in North India, Malacca, 

 and South China. Ellohius (1 sp.), is found in South Eussia 

 and South-west Siberia ; Spalax (1 sp.). Southern Eussia, West 

 Asia, Hungary, Moldavia, and Greece (Plate II., vol. i. p. 218) ; 

 Ehizomys (6 sp.), Abyssinia, North India, Malacca, South China ; 

 Reterocephalus (1 sp.), Abyssinia ; Bathyerges (= Oryderus 1 sp.). 

 South Africa ; Georychus (6 sp.). South, Central, and East Africa ; 

 Heliophobics (1 sp.), Mozambique. 



Family 57.— DIPODID^. (3 Genera, 22 Species.) 



General Distribution. 



Neotropical 

 Sub-regions. 



Nearctic 

 Sub-regions. 



PaLvEARCTIC 



Sub-regions. 



Ethiopian 

 Sub-regions. 



Oriental 

 Sub-regions. 



Australian 

 Sub-rei.ions. 



1.2. 3. 4— 2.3.4 1.2.3— — 



The Jerboas, or jumping mice, are especially characteristic of 

 the regions about the eastern extremity of the Mediterranean, 

 being found in South Eussia, the Caspian district, Arabia, Egypt, 



Vol. II.— 16 



