383 ISLAND LIFE 



had a history of its own, quite distinct from that of the 

 other portions of the Malayan area. 



Special Relations of the Javan Fauna to that of the Asiatic 

 Continent. — These relations are indicated by comparatively 

 few examples, but they are very clear and of great im- 

 portance. Among mammalia, the genus Helictis is found 

 in Java, but in no other Malay country except a recently 

 discovered species in Borneo. But it inhabits also North 

 India ; while two species, Rhinoceros javanicus and Lepus 

 Icurgosa, are natives of Indo-Chinese countries and Java, 

 but not of typical Malaya. In birds there are five genera 

 or sub-genera — Zoothera, Notodela, Crypsirhina, Allotrius, 

 and Cochoa, which inhabit Java, the Himalayas, and 

 Indo-China, all but the last extending south to Tenas- 

 serim, but none of them occurring in Malacca, Sumatra, 

 or Borneo. There is also the very distinct Javanese 

 peacock {Pavo muticus), which inhabits only Java and the 

 Indo-Chinese countries, reaching Perak in the northern 

 part of the Malay Peninsula. 



Here then we find a series of remarkable similarities 

 between Java and the Asiatic continent, quite independent 

 of the typical Malay countries — Borneo, Sumatra, and the 

 Malay Peninsula, which latter have evidently formed one 

 connected land, and thus appear to preclude any in- 

 dependent union of Java and Siam. 



The great difficulty in explaining these facts is that all 

 the required changes of sea and land must have occurred 

 within the period of existing species of mammalia. 

 Sumatra, Borneo, and Malacca have, as we have seen, a 

 great similarity as regards their species of mammals and 

 birds, while Java, though it differs from them in so curious 

 a manner, has no greater degree of speciality, since its 

 species, when not Malayan, are almost all North Indian or 

 Siamese. 



There is however one consideration which may help us 

 over this difficulty. It seems highly probable that in the 

 equatorial regions species have changed less rapidly than 

 in the north temperate zone, on account of the equality 

 and stability of the equatorial climate. We have seen, in 

 Chapter X., how important an agent in producing extinction 



