42 BARBOUR: ZOOGEOGRAPHY. 



like Mysol, is one of the least known and least visited of the islands in its vicinity. 

 Mysol is important neither to the Malayan traders nor to the whites, from a 

 commercial point of view. There are no large settlements on the island, and 

 it is not as frequently visited as are some points on the mainland of New Guinea. 

 Nevertheless, the more or less haphazard distribution of the three species of 

 Hyla would favor the view that accidental introduction may have played a part 

 here. Furthermore it is entirely possible that in the list of reptiles have been 

 included one or more records which should be eliminated. At any rate, the fact 

 remains that, so far as we now know, Mysol shares with Timor-Laut a position 

 on the Malayan zoological frontier, though it remains much more of an enigma 

 as regards the derivation of its fauna than does the other group of islands. 



Halmahera Group. 



None of the other Moluccan Islands is so well known herpetologically as 

 are these; and a most complete resume of their reptilian fauna has been written 

 by Boettger (Abh. Senck. nat. ges. 1900-3, 25, p. 325-375, pi. 14-16). The 

 islands of the group, consisting of the large island of Halmahera, with the small 

 islands of Ternate and Bat j an lying near by, are the ones where Kiikenthal 

 made the collections on which Boettger's paper is based. Other islands of the 

 group less known are Tidor and Morotai. Farther to the south, and quite 

 unknown herpetologically, lies the island of Obi. All of the Halmahera group, 

 with the exception of Obi, are close together, separated from one another by 

 only shallow water, though between Halmahera and Obi there is deep water, 

 from 808 to over 1 ,000 fathoms. Between the group as a whole and New Guinea 

 there is the not unusual condition of a string of small islands with deep water 

 between and about them. Obi was once doubtless connected to the old bridge 

 between Halmahera and New Guinea. The island does not seem ever to have 

 been joined to any other land except this bridge, which is now gone, leaving 

 only many small islands to show where it once existed. As a matter of fact, 

 soundings are so few in this region that it is hard to see what is connected by 

 submarine banks, and what is separated by chasm-like straits. However, a long 

 series of islands, as if a continuation of the southern peninsula of Halmahera, 

 stretches out towards Mysol and Salawati. None of these seem to be separated 

 by water more than 60 fathoms deep. To the northward, again, lies the Papuan 

 island of Gebe, directly between the southeastern peninsula of Halmahera and 

 the Papuan island of Waigiu. The water between these islands seems to be 

 much deeper, though there are no soundings available in a direct line between 



