BULLETIN UNITED STATES GEOLOGICAL SURVEY. 



V T ESPERTILIOXID^E. Cosmopolitan. Represented by the cosmopolite genus Yespertilio. 

 EMBALLONURID^:. Warmer parts of the world. Represented by the genus Taphozous. 

 CENTETUXE. Confined to Madagascar except one genus (Solenodon) in the West In dies. 



Represented in Madagascar by nearly a dozen species. Genera : Centetes^ 



Hemicentetes, Ericulus, Oryzorictes, Echinops. 

 SORICIDJE. The whole world, except South America and Australia. Represented in 



Madagascar by one or two species of Crocidura, a genus found in Africa, 



and the warmer parts of the eastern hemisphere generally. 

 MURHXE. Cosmopolitan. Represented by several genera of African affinities, namely,. 



Nesomys, Brachytarsomys, Hypogeomys. 



VIII. ANTARCTIC REALM. 



The Antarctic Eealrn is geographically almost wholly oceanic, and its 

 fauna hence consists almost exclusively of marine or pelagic species. 

 It necessarily embraces not only the Antarctic Zone, but a large part 

 of the cold south-temperate, since very few of its characteristic species 

 are wholly restricted to the Antarctic waters. It will hence include not 

 only the few small groups of Antarctic Islands, but also Tierra del Fuego- 

 and the Falkland Islands, and perhaps also the extreme southern shores 

 of South America, while some of its characteristic forms also extend to 

 New Zealand, and even Australia and the Cape of Good Hope. The 

 only mammals that can be considered as strictly characteristic of this 

 region are Pinnipeds and Cetaceans, of which several genera of each 

 are almost wholly restricted to it. A " South Frigid", "Antarctic 77 , or 

 "South Cireurnpolar" "Zone", "Begion", or "Bealm", has been recog- 

 nized by various writers for the marine invertebrates, and, by vou 

 Pelzeln for birds, with limitations much as here assigned. While the 

 number of species peculiar to it is small, it is large relatively to the 

 whole number represented, especially in the colder latitudes. There is, 

 of course, a broad belt along its northern border of a transitional char- 

 acter, where Antarctic types overlap the range of groups characteristic 

 of south-temperate latitudes. 



One of the most important features of the South Circumpolar or Ant- 

 arctic Bealm is the resemblance of its life to the marine life of the Arc- 

 tic or North Circumpolar Bealm. While perhaps in no case are the 

 species identical, the genera are frequently the same, not only among 

 the mammalia, but among invertebrates. This is especially significant 

 as regards the mammalia, since the terrestrial mammals of the extreme 

 north and extreme south present no such parallelism, but the utmost 

 divergence. Among Pinnipeds, most of the genera are peculiar to either 

 the northern or southern waters, but in several instances the genera of 

 the two regions are strictly representative. Thus, Otaria and Arctoce- 

 phalus of the Southern Seas are represented in the Northern by Eume- 

 topias and Callorhinus, Zalophus and Macrorhimis are both Northern 

 and Southern. Stenorhynchus, Lobodon, Leptonyx, and Ommatophoca are 

 strictly Southern, while Phoca, Haliclicerus, Erignathm, Cystophora, 

 Monachus, and one or two others, are strictly Northern, as are also the 

 Walruses. The Mysticete, or Baleen Whales, among Cetaceans, have 



