PARTULA, TAHITI. 179 



not of Lamarck. Mat at a HARTMAN, t. c. p. 14, type P. rosea 

 Brod. ; not Matuta Fabric! us. 



The typical group of Partula is restricted to the Society 

 and Hervey Islands. Each island has its minor type of 

 shell, except Moorea and Tahaa, which have Tahiti an and 

 Raiatean types respectively ; 'but the entire series is so closely 

 interrelated that the named subgenerie divisions proposed by 

 Dr. Hartman cannot be sustained. 



A small group of white, translucent species includes 



No. 9, P. hyalina Brod. Tahiti, Hervey and Austral 

 Islands. 



No. 16, P. clara Pse. Tahiti. 



No. 17, P. attenuata Pse. Tahiti and Raiatea. 



No. 44, P. annectens Pse. Huaheine. 



These forms may have some exceptional means of distribu- 

 tion, or they may be conservative stocks, which have altered 

 little since the original radiation over the mountain ranges 

 which are now islands. They approach the simply colored 

 southwestern forms of Partula, such as those of the Solomon 

 Islands, in appearance, and seem to be little-changed mem- 

 bers of an old stock. 



The species are here treated in geographic order, as follows : 



1. Tahiti, species 9 to 17. 



2. Moorea, species 18 to 21. 



3. Raiatea and Tahaa, species 22 to 41, 8. 



4. Huaheine, species 42 to 44, 7. 



5. Borabora, species 45. 



6. Species of uncertain habitat, species 46 to 50. 



1. Partulce of Tahiti. 



"On Tahiti, the largest island in the group, we find eight 

 species only, six of which are endemic. One (P. clara}, 

 which has a limited range, appears to be gradually becoming 

 extinct. Four species (P. filosa, nodosa, producta and stolida) 

 are each restricted to a single valley. All the above species 

 are well-defined, and exhibit but little variation. On the 

 contrary, P. otaheitana, which has its centre of distribution 



