384 ISLAND LIFE 



SiKcial Relations of the Javcin Fctunct to tlicit of the Asiatic 

 Gooitinent. — 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, though it inhabits 

 also North India ; while two species. Rhinoceros javanicus 

 and Lc-ptis kurgosa, 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 

 Tenasserim, but none of them occurring in Malacca, 

 Sumatra, or Borneo. There are also two species of birds 

 — a trogon {Harpaetes oreshios), and the Javanese peacock 

 {Pavo nmticus), which inhabit only Java and the Indo- 

 Chinese countries, the former reaching Tenasserim and the 

 latter Perak in the Malay Peninsula. 



Here, then, we find a series of remarkable similarities 

 between Java and the Asiatic continent, quite independent 

 of the tyj)ical 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 ex]3laining 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 

 and modification of species must have been the repeated 

 changes from cold to warm, and from warm to cold con- 



