SUMATRA. 11 



The collections of the Museum have, of course, been consulted freely, and 

 references have been made to a few of the indi\'iduals contained in them. It is 

 unfortunate that time does not permit the inclusion of notes on all the East 

 Indian specimens available for study here. Many of these were brought back 

 by the earlier American voyagers, and were sent by Louis Agassiz to Jan in 

 Milan for identification; others, still, came here in early exchanges from the 

 Paris museum, and were marked as types by A. Aug. Dumeril. Wliile not 

 holotypes in the sense in which the word type is commonly used now, they are 

 undoubtedly a part of the typical series of many of the species described by 

 Dumeril and Bibron in their Erpetologie general. 



Sumatra. 



The first island to be discussed, with direct regard to the relationships of 

 its reptiles and amphibians, is Sumatra. A few words regarding its physical 

 pecuUarities are worth while. The island lies nearer to the Malay Peninsula 

 than any other of the East Indies, the straits of Malacca in many places being 

 less than fifty miles wide. There is a tradition that the lands joined almost 

 within historic times. It is nearly one thousand miles long ; and varies in width 

 from between less than one hundred miles in the mountainous district of Atjeh 

 in the north, to about two hundred miles at the region opposite the lower end 

 of the Malay Peninsula. The main trend is from northwest to southeast, and 

 throughout its entire length extends a backbone moxmtain range, which runs 

 close to the western or Indian Ocean side of the island. This range, it is interest- 

 ing to notice, is almost exactly parallel to the mountainous backbone of the 

 Malay Peninsula, and to the series of mountainous islands which lie in the 

 Indian Ocean off the coast of Sumatra in a long series, beginning with Simalur 

 at the north and ending with Engafio towards the south. These may indicate 

 corrugations along which foldings of great extent have occurred, but there is no 

 direct evidence at hand on this point. 



The configuration and foi-ni of the shore-Une and bays of the islands off 

 Sumatra, and of Sumatra itself, and more especially the suggestions which one 

 gets from the soundings shown on the chart, lead one to suppose that this has 

 been an area of general subsidence. It seems probable that the island of Simalur 

 was connected with Sumatra by way of the Banjak Archipelago; that Nias was 

 connected directly with Sumatra, quite independently of Simalur; and that the 

 Mentawei Islands were connected together, and with Sumatra, through the 



