ALLEN ON GEOGRAPHICAL DISTRIBUTION OF MAMMALS. 349 



Summary. 



Whole number of genera ^ 90 



Mainly restricted to the region 31 



Of general distribution throughout the American Tropical Realm 41 



Occurring alao over much o^the South American Temper.ate Realm 9 



Occurring also in the warmer parts of the North Temperate Region 6 



Tropicopolitan '. 3 



Cosmopolitan 6 



IV. SOUTH AMERICAN TEMPERATE REALM. 



What is here termed the South American Temperate Bealin embraces 

 all that portion of the South American continent and adjacent islands 

 not included in the American Tropical Kealm as already defined. It 

 coincides very nearly with Mr. Wallace's " South Temperate America 

 or Chilian Subregion ".* Its northern limit on the Atlantic coast is 

 near the thirtieth parallel. On leaving the Atlantic coast, the north- 

 ern boundary passes obliquely northwestward, rising in the region of the 

 Chaco Desert, to, or possibly a little beyond, the Tropic of Capricorn. 

 Again descending to about the twenty-fifth parallel, it turns abruptly 

 northward and eastward, along the eastern border of the Andean 

 chain, nearly to the fifth degree of south latitude, near which point it 

 strikes the Pacific coast. It thus embraces a large part of the great 

 Andean plateau, with the neighboring coast region to the westward, 

 nearly all the La Plata plains, and the region thence southward to 

 Tierra del Fuego, which belongs also to this region. 



As contrasted with the Tropical Eealm to the northward, it is charac- 

 terized, in respect to mammals, by the absence of all Quadrumana and 

 the paucity of Edentates and Marsupials, there being neither Sloths 

 nor Anteaters, while only two or three species of Opossums barely ex- 

 tend over its borders ; the absence of all genera of Leaf-nosed Bats, and 

 of not less than a dozen important genera of Eodents, the Coatis, the 

 Kinkajou, the Tapirs, and many other genera characteristic of the 

 American tropics.t As noted by Mr. Wallace, it is further character- 

 ized by the possession of the entire family of the Cliinchillidce, the gen- 

 era Auchenia, Habrocomus, Spalacopus, Actodon, Ctenomys, DolicUotiSj 

 Myopotamus, Chlamadophorus, to which may be added the marine gen- 

 era Otaria, Arctocephalus, Morunga, Lobodon, and Stenorhynchus, very 

 few of which range beyond the northern border of this region. The 

 Spectacled Bear is also confined to it, and here are also most largely 

 developed the Murine genera Calomys, Acodon, and Eeithrodon. 



Although one of the smallest of the primary regions, it is apparently 

 divisible into two more or less well-marked provinces, which may be 



* Geog. Distr. Animals, vol. ii, p. 36, and map of the "Neotropical Region". 



tAmong the genera of the Brazilian Region here unrepresented are, aside from the 

 Quadnitnana, Cercoleptes, Nasua, Tapirus, Bradypm, Chcclopus, Myrmecopliaga, Taman- 

 dua, CyclotJiurus, Phyllostoma, Glossopliaga, Arctibeus, Dysopes (and other genera of Chi' 

 roptera), Hydrochcems, Cercomys, Dactylomys, Loncheres, Echimya, Coelogenys, Dasyprocta, 

 Chcetomys, Cercolabes, Lepus, Sciurus, Habrothrix, Oxymycterus, Holochilus, etc., = 27 -f-. 



