FORMER PACIFIC CONTINENT. 235 



beyond Java and Borneo, do essentially form a part of a 

 former Australian or Pacific continent, although some of 

 them may never have been actually joined to it. This 

 continent must have been broken up not only before the 

 Western islands were separated from Asia, but pro- 

 bably before the extreme south-eastern portion of 

 Asia was raised above the waters of the ocean ; for a 

 great part of the land of Borneo and Java is known to 

 be geologically of quite recent formation; while the very 

 great difference of species, and in many cases of genera 

 also, between the productions of the Eastern Malay 

 islands and Australia, as well as the great depth of the 

 sea now separating them, all point to a comparatively 

 long period of isolation." 



" It is interesting to observe among the islands them- 

 selves how a shallow sea always intimates a recent land 

 connection. The Aru islands, Maisol and Waigiou, as 

 well as Jobic, agree with New Guinea in their species of 

 mammalia and birds much more closely than they do 

 with the Moluccas, and we find that they are all united to 

 New Guinea by a shallow sea. In fact, the lOO-fathom 

 line round New Guinea marks out accurately the range 

 of the true Paradise birds. 



" It is further to be noted — and this is a very interesting 

 point in connection with theories of the dependence of 

 special forms of life on external conditions — that this 

 division of the Archipelago into two regions character- 

 ized by a striking diversity in their natural productions, 

 does not in any way correspond to the main physical or 

 climatal divisions of the surface." We will further 

 quote only the following : " Borneo and New Guinea, as 

 alike physically as two distinct countries can be, are 



