364 BULLETIN UNITED STATES GEOLOGICAL SURVEY. 



.Restricted to Sumatra 2 



Restricted to Java L 



Restricted to the Philippines . 2 



Restricted to the Philippines and Celebes 1 



Occurring only in Celebes 2 



Nou -pi acental genera 1 



VI. AUSTRALIAN REALM. 



The Australian Realm will be here restricted so as to embrace none 

 of the islands situated to the westward of the Moluccas. The Molucca 

 Group forms a transitional link between the Indo- African and the Aus- 

 tralian Realm, but they are faunally more closely allied to the latter than 

 to the former. These islands embrace, excluding Chiroptera and species 

 probably or known to have been introduced by man,'* only a single 

 genus (Sorex) of Placental Mammals, while two genera of Papuan Mar- 

 supials (Cuscus and Belideus) are abundantly represented. 



The Australian Realm, considered as a whole, is made up of very 

 heterogeneous elements, its land-surface consisting of islands, many of 

 them of small size and widely scattered. The mammals are almost 

 wholly limited to its three larger constituents, Australia, Tasmania, and 

 New Guinea, and a few of the larger islands in close proximity to them. 

 Among the prominent types very generally represented throughout all 

 of these areas are several wide-ranging (almost tropicopolitan) genera 

 of Bats, which, in consequence of their wide geographical range, wholly 

 fail to be distinctive, and may hence be safely ignored in the following- 

 general analysis of the region. The marine species (the Dugong and 

 various species of Seals) are likewise of small importance in the present 

 connection, since they are all wide-ranging species, not properly charac- 

 teristic of the region. After these eliminations, we have left a few 

 genera of Muridce and the distinctively characteristic implacental mam- 

 malia. The latter, with the exception of a single family (Dldelpliidce, 

 occurring now only in the warmer parts of the two Americas), are found 

 nowhere else, and hence give to the region an exceptional distinctness 

 as a primary zoogeographical region. The numerous groups of small, 

 widely scattered islands, usually considered as collectively forming the 

 Polynesian Region, being destitute of mammalia, need not be here fur- 

 ther considered. 



New Zealand, situated more than a thousand miles to the southeast- 

 ward of Australia (its nearest large land-area), is also wholly deficient 

 in characteristic forms of mammalia ; the only representatives of this 

 class, aside from Seals and Bats, being a Rodent, supposed, rather than 

 certainly known, to be found there. The Seals are wide-ranging species, 

 and of the two species of Bats, one has Australian and the other South 



* These include, besides the common domestic species, Cynopithecus nigrescem, Viverra 

 tangalunga, JBabirusa alfurus, and Cervus Mppelaphus var. moluccensis, considered by Mr. 

 Wallace as " probably" or " almost certainly" introduced by man, since they are spe- 

 cies " habitually domesticated and kept in confinement by the Malays ". Geogr. Dist. 

 Anim., vol. i, p. 417. 



