264 PROCEEDINGS OF THE MALACOLOGICAL SOCIETY. 



The full classification is as follows : — 



Hemiphccdusa Group. Zaptyx Group. 



1. Megalophadusa. 1. Hemizaptyx. 



2. Heiniphcedusa. 2. Heterozaptyx. 



3. Formosana. 3. Zaptyx. 



4. Tyrannophcadusa. 4. Stereozaptyx } 



5. Nesiophcedusa} 5. Parazaptyx} 



6. LuchuphcBdusa . 6. Metazaptyx. 



7. OophcBdusa. 7. Diceratozapt]/x} 



8. Stereophcedusa. 8. OUgozaptyx} 



9. Idiozaptyx.^ 

 Euphcedusa Group. 10. Selcnozaptyx} 



1. Pseudonenia. H- Thaumatoptyx. 



2. Euphcedusa. 



" In Korea, Japanese forms dominate over Chinese forms. The 

 submergence of the straits between Kiu Siu and Korea is hence 

 a geologically recent event, probably not earlier than the Pliocene 

 period. All the genera and sub-genera of the Korean moUuscan fauna 

 occur in Japan. In the Clausilias all the species [five in number] of 

 Qiielpart and Korea belong to Euphcedusa, a group of minor importance 

 in Japan, but extending furtJier north on tlie Asiatic mainland than 

 any other group of Claiisilia'^ (Pilsbry 48). 



Malay Peninsula and East Indian Islands. — The ^lalay Peninsula 

 forms practically tlie first of the group of great islands which is 

 continued by Sumatra and Java. The fauna is not very well known, 

 but the Clausilia belong only to those groups which occur on the 

 islands. About four or five species, all Pseudonenia or Euphcedusa, 

 have been described from Perak, Penang, Kehmtan, and elsewhere. 



Further exploration of tlie great East Indian islands will no 

 doubt add much to our knowledge of their Mollusca. But we already 

 know enough to see tliat as we go eastward Clausilia steadily dies 

 out. Euphcedusa and Pseudonetiia include the bulk of the species. 

 Acrophccdusa, Pttg., is peculiar to Java, and Paraphcedusa, Bttg.. to 

 Celebes. Borneo contains two species of Eormosa7ia, a Chinese and 

 Formosan group. No species appears to be common to any two 

 islands, except cuminqiana, Pfr., which in one or other of its varieties 

 occurs in the Philippines, Sulu Islands, Celebes, Sangir, Halmaheira, 

 and Ternate, and recondila, Sykes, which is common to Sumbawa and 

 Halmalieira. It is remarkable that so far only one species has been 

 discovered in the Philippines, which are not only nearest to Formosa 

 but have also been better searched than any other group. 



From Sumatra we have 7 species, Java 10, Borneo 4, Celebes 10, 

 Philippines 1, Sulu 2, Sangir 1, Sumbawa 1, Halmaheira and 

 Ternate 2, Selangor 1. Molluscan lists from the following islands 

 have been published, but do not contain any Clausilia : Lombok, 

 Buru, Tenimber, Batchian. Nor has any species as yet been 

 described from New Guinea, though the genus may well exist in the 

 higher mountain ranges of that great island, and anything seems 



^ Peculiar to Loo Choc group. 



