AMBON. 37 



in the Moluccas. For this reason, without material at hand for comparison, 

 it is impossible to say whether the Riopa occurring on Ambon is Merrem's 

 R. rufescens, long known from New Guinea and Queensland, or whether it 

 represents R. mentovarium (Boettger), hitherto found only on Halmahera, and 

 replacing there R. rufescens, which was previously reported from that island. 

 Boulenger in a recent letter has written me that specimens from Ambon are 

 different from those from Halmahera. Specimens from Ceram, Obi, and other 

 neighboring islands, however, still require close comparison. 



Cryptohlepharus houtonii (Desj.) occurs also on both of the islands. 



A list of the snakes follows : — 



Python amethystinus (Schn.), of Papuan derivation. 



P. reticulatus (Schn.), of Malayan derivation. 



Enygrus carinatus (Schn.), of Papuan derivation. 



Brachyorrhus alhus (Linne), of Papuan origin. 



Stegonotus modestus (Schlegel). Boulenger writes me that Ambon speci- 

 mens can not be distinguished from Papuan. 



Oligodon bitorquatus Boie, a Javan species, like others omitted here, and 

 probably erroneously reported from Ambon. 



Hurria rhynchops (Schn.), a freely swimming form of Malayan origin. 



Boiga irregularis (Bechstein), specifically Papuan in origin, occurring through- 

 out the Moluccas. The genus Boiga is, of course, Malayan, as is also Python. 



Chrysopelea rhodopleuron Boie, Moluccan representative of a Malayan 

 genus. 



Of the amphibians, Rana grunniens Daudin has the same impossible 

 distribution mentioned before, Java and Ambon. 



Phrynomantis fusca Peters is found only upon Ambon and Batanta, and 

 is probably incorrectly placed in this wholly African genus. Hyla amboinensis 

 Horst is confined to Ambon and Mysol. H. dolichopsis (Cope), a wide-ranging 

 Papuan species which, as we now know, has been transplanted by human agency 

 as far as Java, occurs also on both islands. 



To sum up in a few words the conditions here, we find that, in spite of 

 geographic proximity to Papua, we are still in what may be called the transition 

 zone. Timor-Laut, these islands of the Moluccas, and even, as we shall show 

 later, Mysol, all have a number of Malayan forms, as well as generally even more 

 Papuan forms, which are the ones we should expect to predominate to a greater 

 extent than is actually the case. We are now, to be sure, on the extreme hmit 

 of the true Malayan herpetological fauna; and, although it is so conspicuous 



