PARTULA. 165 



are investigated anatomically, a further generic division 

 may foe made. There are two rather dissimilar forms of 

 kidney among the Polynesian species, though at present we 

 do not know enough species anatomically to utilize this fact 

 m taxonomy. By conchological characters nine divisions are 

 indicated, herein called "sections." In all cases these sec- 

 tions are geographically limited to single island-groups, or 

 to several adjacent groups. Five of the nine sections of 

 Partula have already been named by Dr. Hartman, who 

 unfortunately used preoccupied names, and in most cases 

 understood the groups in limits different from mine. He 

 also split the typical group of Partulas into numerous sub- 

 genera which seem to me superfluous. The subgenera here- 

 in established are as follows. 



MARQUESANA Pilsbry. Embryonic whorls coarsely pitted 

 along the spirals ; post-embryonic whorls with very well de- 

 veloped spiral lines ; lip .thin but often widely reflexed ; colors 

 not bright, a subperipheral band frequently present, but 

 no others; cuticle thin, often deciduous. Type P. gany- 

 medes. This group includes all known Marquesan species, 

 no. 1 to 6. 



LEPTOPARTULA Pils. Shells ovate with short spire, com- 

 posed of few (4 to 4^/2) whorls; very thin and fragile, sub- 

 transparent, pale colored ; aperture large, ovate, toothless, 

 lip expanded, not thickened. Type P. arguta. Huaheine and 

 Raiatea, Society Is. Species no. 7 and 8. 



PARTULA s. sir. Shell ovate, usually solid and with opaque 

 coloring, often in bands or streaks; lip thickened within, the 

 callus not extending to the upper insertion ; parietal wall 

 often toothed. Society, Austral and Hervey Is., species 9- 

 52, and probably Samoan and Tonga Is., species 60-62. 



SAMOANA Pils. The shell is very openly umbilicate, dex- 

 tral or sinistral, with flatly reflexed lip and no teeth. Type 

 P. canalis. Samoan Is., species 53 to 58. 



THAKOMBAUA Pils. Shell rimate, long-ovate, the later 

 whorls sculptured with coarse spiral cords. A low callous 

 tubercle on the parietal wall far within. Type P. lirata, no. 



