520 



GEOGRAPHICAL ZOOLOGY. 



[part IV. 



J)i]jlommatina (18 sp.) inhabits India to Burniah, and the 

 greater part of the Australian region ; the number of species has 

 now been doubled, and one has been discovered in the island 

 of Trinidad ; Clostophis (1 sp.), Moulmein ; Faxillus (3 sp.), 

 Borneo, Hong Kong, and Loo Clioo Islands. 



Family 20.— CYCLOSTOMID.^. (41 Genera, 1009 Species.) 



(1865.) 



GeXEK.\L DI8TUIBTJTION. 



This extensive group, comprising the largest of the opercu- 

 lated land-shells, is especially characteristic of the Oriental 

 region, which possesses 25 genera, no less than 12 of them being 

 wholly confined to it. The Neotropical region comes next, with 

 15 genera, 9 of which are peculiar; but a large number of 

 these are confined to the West Indian Islands, South America 

 itself being very poor in this group. Tlie Paloearctic region 

 has 3 peculiar genera ; the Ethiopian and Australian 1 each. 

 The Nearctic region has but a smgle AYest Indian species in 

 Florida. The distribution of the genera is as follows : — 



Peculiar to or characteristic of the Oriental region are, Opis- 

 thoporus (11 sp.), Mhiostoma (6 sp.), Ahjcaeus (39 sp.), Opisthos- 

 toma (1 sp.), Hylocistis (3 sp.), Pterocyclos (19 sp.), extending to 

 the Moluccas ; Aulopoma (4 sp.), Dermatocera (4 sp.), Lcptopoma 

 (54 sp.), extending west to the Seychelles and east to the Mo- 

 luccas and New Guinea; CyclopJiorus (163 sp.), most abundant 

 in the Oriental region, but ranges to Japan, to Chili, and all 

 Tropical America, over the whole Australian region, and to 

 Natal and Madagascar ; Gatauliis (15 sp.), confined to Ceylon, 

 the Neilgherries and Nicobar Islands ; Rliapliaulus (4 sp.), 

 Penang to Ceram ; Streptauhis (1 sp.), Arinia (3 sp.), Pi/pinella 

 [2 sp.), Pvpma (24 s«p.), half in North India to Philippines and 



