122 BULLETIN OF THE 



lip at the aperture; axial lamina visible (ami sometimes double) at the aper- 

 ture, continuous for one or two turns on the axis within ; whorls ample, with- 

 out lauiinic (other than those mentioned) internally. Type Pupa decumana 

 Fer., Castle Island, Bahamas. (Figure 4.) 



S. pannosa Maynard, 5. copia, S. nana, and S. lineala of the same author 

 belong to this group, which Maynard regards as characteristic of the Cayman 

 Islands, Bahamas. 



Subgenus MAYNARDIA Dall, 1894. 



Armature resembling that of Strophiops, but the parietal tooth short, not 

 exceeding three times its height, and rather abruptly terminated at the inner 

 end. Type S. neglecta Maynard, Andros Island, Bahamas. (Figure 1.) 



Strophia alba Maynard, S. protea Gundl., S. maritima Pfr., -S. cyclostoma 

 Kiister, and S. incana Binne}', belong in this group, which is common to Cuba, 

 the Bahamas, and South Florida. C. Agassizii also seems to belong here, 

 though somewhat less characteristic than the recent species. 



Subgenus DIACERIOX Dall, 1894. 



Shell with both laminae visible at the aperture, the axial lamina as in 

 typical Strophiops; the parietal rather low and single at the aperture, double 

 within, the outer branch more prominent near the aperture, the inner more 

 prominent in the penultimate whorl, the pair prolonged inwardly for one or 

 two whorls ; whorls ample, without other internal laniinaj. 



Type Strophia Dalli Maynard, Inagua Island, Bahamas. (Figure 2.) Turbo 

 alvearia Dillwyn, and Strophia pallida Maynard, also belong here. The group 

 is reported so far only from Inagua Island, Bahamas. 



Subgenus EOSTROPHIA Dall, 1890. 



Shell without axial or parietal lamin.ne, otherwise as in Strophiops. Fossil 

 of the Older Miocene. Type E. anodonta Dall, Tampa silex beds. Cf. Trans. 

 Wagner Inst., III. 12, August, 1890. 



While Cerion in the broad sense forms a very recognizable group, and one 

 which remounts to a notable antiquity, the divisions above mentioned, appar- 

 ently constant and easily identified, are of at least as much systematic value as 

 three fourths of the "generic" subdivisions made of late among the Pulmonata, 

 the convenience of which I should hesitate to deny. I have therefore thought 

 it desirable that names should be applied to them, and attention thus invited 

 to the very interesting gronji under consideration. 



We owe to von Martens (Malak. Bl., VI. 209) the interesting observation, 



