X CELEBES — THE MOLUCCAS 311 



which Ohha and Ohhina occur, shows decided relationship with 

 the Philippines, while the occurrence of three Chloritis and one 

 Planispira tend to approximate S. Celebes rather with the 

 Moluccas. 



The islands eastward of Java^ from Bali to Timor Laut and 

 the Tenimber Is., present no trace of individual peculiarities ; 

 they simply carry on the Indo-Malay fauna as though along a 

 great peninsula. Even Timor, surrounded as it is on all sides by 

 sea of profound depth, shows no sign of possessing even one 

 peculiar genus. Amphidromus^ perhaps the most characteristic 

 of all Indo-Malay genera, occurs throughout, diminishing in 

 numbers as we go eastward (Bali, Lombok, and Sumbawa 4 sp., 

 Timor 2 sp., Timor Laut 1 sp.), while Plectotropis reaches no 

 farther than Flores and Timor. The tubed operculates are alto- 

 gether wanting. In Timor Laut we have Moluccan influence 

 appearing in 3 Chloritis^ and there is one (supposed) Corasia. 

 Two Helices of a marked Australian type (Rliagada) occur, one 

 in Flores, the other on Dama I., south-west of Timor. The con- 

 figuration of the sea bottom (see map) would lead us to believe 

 that the north-west coast of Australia once stretched a good 

 deal nearer to these islands. 



The Moluccas^ taken as a whole, constitute a transition region 

 between the Indo-Malay and the Papuan faunas, uniting, to a very 

 considerable extent, the features of both. They fall into two 

 well-defined groups. The northern, or Ternate group, consists of 

 Gilolo (Halmahera), Batchian, and the outlying islands as far 

 south as and including Obi major. The southern, or Amboyna 

 group, consists of Burn, Ceram, Amboyna, and the chain of islands 

 to the south-east of Ceram, as far as, and including the Ke Is. 



The Ternate group shows decidedly closer relations with New 

 Guinea than the Amboyna group. Thus, among the Helices^ the 

 markedly Papuan genus Papuina is represented by 7 species in 

 the Ternate group, but by 1 in the Amboyna group. Again, the 

 Cristigihha section of Planispira^ which is a Papuan form, has 

 4 representatives in the northern group, but only 1 in the 

 southern. Certain points of connexion with Celebes come out 

 in the southern group which are wanting in the northern ; thus 

 of Chloritis there are 8 species in Amboyna, in Ternate, 3 in 

 Celebes. 



In the Moluccas the Helicidae, for the first time as we move 



