Physical G-eogeaphy. 29 



and Lombock, might each exhibit an almost unmixed sample 

 of the productions of the continents of which they had direct- 

 ly or indirectly once formed a part. 



In the Malay Archij)elago we have, I believe, a case exact- 

 ly parallel to that which I have here supposed. We have in- 

 dications of a vast continent, with a peculiar fauna and flora, 

 having been gradually and irregularly broken up ; the island 

 of Celebes j^robably marking its furthest westward extension, 

 beyond which was a wide ocean. At the same time Asia ap- 

 I^ears to have been extending its limits in a south-east direc- 

 tion, first in an imbroken mass, then separated into islands as 

 we now see it, and almost coming into actual contact with the 

 scattered fragments of the great southern land. 



From this outline of the subject, it will be evident how im- 

 portant an adjunct Natural History is to Geology ; not only 

 in interpreting the fragments of extinct animals found in the 

 earth's crust, but in determining past changes in the surface 

 which have left no geological record. It is certainly a won- 

 derful and unexpected fact, that an accurate knowledge of the 

 distribution of birds and insects should enable us to map out 

 lands and continents which disappeared beneath the ocean 

 long before the earliest traditions of the human race. Wher- 

 ever the geologist can explore the earth's surface, he can read 

 much of its past history, and can determine approximately its 

 latest movements above and below the sea-level; but wher- 

 ever oceans and seas now extend, he can do nothing but spec- 

 ulate on the very limited data afforded by the depth of the 

 waters. Plere the naturalist steps in, and enables him to fill 

 up this great gap in the past history of the earth. 



One of the chief objects of my travels was to obtain evi- 

 dence of this nature ; and my search after such evidence has 

 been rewarded by great success, so that I have been enabled 

 to trace out with some probability the past changes which 

 one of the most interesting parts of the earth has undergone. 

 It may be thought that the facts and generalizations here 

 given would have been more appropriately placed at the end 

 rather than at the beginning of a narrative of the travels Avhich 

 supplied the facts. In some cases this might be so, but I 

 have found it impossible to give such an account as I desire 

 of the natural history of the numerous islands and groups of 



