358 BULLETIN UNITED STATES GEOLOGICAL SURVEY. 



from the Lower Indus to the Formosa Straits, the islands of the Indian 

 Archipelago, as well as Formosa, the Philippines, Celebes, and all of the 

 Sanda Islands. As far as the mammalia are concerned, only two primary 

 subdivisions, or provinces, seem to be recognizable, the one a Northern, 

 or Continental, the other a Southern, or Insular ("Malayan"). The 

 former, or Continental, includes nearly all of the Hindostan and Indo- 

 Chinese Peninsulas, excepting the extreme southern border of the latter 

 and Malacca. These areas belong to the Insular Province, which com- 

 prises not only Borneo, Sumatra, and Java, but all of the above-named 

 smaller islands to the eastward, except Formosa, which pertains to the 

 Continental Province. 



The long, narrow Malaccan Peninsula is almost insular in position and 

 character, and agrees far better, climatologically, and in its productions, 

 with Borneo and Sumatra, than with the mainland to the northward, as 

 does, in fact, the extreme coast border of the mainland, embracing Lower 

 Cochin China, Cambodia, etc. The small outlying islands to the east- 

 ward have nothing in common with the Australian Realm (if we exclude 

 the wide-ranging CMroptera and a few marine forms, which are, of all 

 mammals, of least importance in a zoogeographical point of view), except 

 the single Marsupial genus Cusgus occurring in Timor and Celebes, while 

 no placental mammals except Sus, a few Murine genera, the Dugong, and 

 Chiroptera, reach any portion of the Australian Eealm. Malacca, Borneo, 

 and Sumatra form the central and typical portion of the Insular or Malayan 

 Province, being, from their larger area and closer proximity to each other 

 and to the tropical mainland, far richer in genera and species than the 

 smaller and more remote islands to the southward and eastward. Even 

 Java has a less varied mammalian fauna than either Borneo or Samatra, 

 and thus differs from them negatively rather than by the possession of 

 peculiar types. Thence eastward, throughout the Sunda Islands, the 

 differences are almost wholly such as result from the small size and 

 isolated position of these insular areas, through a gradual disappearance 

 of many types present in the larger islands. The Philippines, for simi- 

 lar reasons, lack a large proportion of the genera found in the central 

 portion of the province, while those they do possess, with few excep- 

 tions, are such as are common to the larger areas. The few that are 

 peculiar are Indian, rather than Australian, in their affinities. 



Celebes and Timor contain one strictly Australian genus {Cuscus, rep- 

 resented by several species), but the few other mammals found there 

 are either Indian or possess strictly Indian or Indo-African affinities. 

 Hence I fail to see any good reason for assigning Celebes and all the 

 smaller Sunda Islands to the Papuan Province, as Mr. Wallace and others 

 have done, but abundant evidence that such is not their real affinity. 

 Even Mr. Wallace's own tables of distribution show at a glance the wide 

 disassociation of these islands from the Papuan fauna, and their much 

 nearer relation to the Indian, there being but one typically Australian 

 or Papuan form represented in any of them, while none of the placental 



