122 BULLETIN OF THE 



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

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

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

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



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

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

 Islands, Bahamas. 



Subgenus MAYXARDIA 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, 5. protea Gundl., ^\ marihma Pfr., S. cydostoma 

 Kiister, and 5. incana Binney, 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 DIACEEION Dall, 1894. 



Shell with both lamina 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 ]ienultimate whorl, the pair prolonged inwardly for one or 

 two whorls ; whorls ample, without other internal laminae. 



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

 alcearia Dillwyn, and Strophia pallida IMaynard, also belong here. The group 

 is reported so far only from Inagua Island, Bahamas. 



Subgenus EOSTROPHIA Dall, 1890. 



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

 of the Older Mi(5cene. Type E. anodonta Dall, Tampa silex beds. Cf. TrariS. 

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



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

 which remounts to a notable antiquit}^ 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 Pulnumata, 

 the convenience of which I sho\ild hesitate to deny. I have therefore thought 

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

 to the very interesting group under consideration. 



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



