10 BULLETIN 68, UNITED STATES NATIONAL MUSEUM. 



A^ Columellar folds two— Continued. 

 Shell not umbilicated — Continued. 



Surface polished, marked by very faint lines of growth and microsropic 

 spiral striations — Continued. 

 Basal fasciole absent. 



Subgenus Eulimella Forbes, 1846 (6). 



Type, Eulimella crussula Forbes, ^E. scillx Scacrhi. 



Aperture subquadrate. 



Section Eulimella Forbes, s. s. 

 Aperture suboval. 



Section Cossmannica Dall and Bartsch, 1904 (7). 

 Type, Pyramidella clandestina Deshayes. 

 A^ Columellar fold one. 

 Shell umbilicated. 



Surface polished, or with fine lines of growth and microscopic spiral striations. 

 Peripheral sulcus absent. 



Subgenus Orinella Dall and Bartsch, 1904 (8). 

 Type, Orina pinguicula A. Adams. 



Peripheral sulcus present. 



Subgenus Sulcorinella Dall and Bartsch, 1904 (8). 



Type, Pyramidella (Sulcorinella) dodona, Dall and 

 Bartsch. 

 Shell not umbilicated. 



Large, heavy, elongated shells. 

 Surface spirally lirate. 



Subgenus Actaeopyramis Fischer, 1885 (9). 

 Type, Monopiygma striata Gray. 



Slender, medium sized shells. 



Surface polished, marked by fine lines of growth and microscopic spiral 

 striations. 



Postnuclear whorls increasing slowly in size at first, then rapidly, 

 lending the shell a mucronate appearance. 



Subgenus Styloptygma A. Adams, 1860 (10). 

 Type, Monoptygma stylina A. Adams. 



Postnuclear whorls increasing regularly in size. 



Subgenus Syrnola A. Adams, 1860 (11). 

 Type, Syrnola gracillima A. Adams. 



Aperture suboval. 



Section Syrnola A. Adams, s. s. 



Aperture subquadrate. 



Section Stylopsis A. Adams, 1860 (12). 

 Type, Stylopsis typica A. Adams. 



Surface spirally striated. 



Subgenus Iphiana Dall and Bartsch, 1904 (8). 

 Type, Syrnola densistriata Garrett. 



Surface axially and spirally striated with a strong spiral keel at the sum- 

 mit of the whorls. 



Subgenus Syrnolina Dall and Bartsch, 1904 (8). 

 Type, Syrnola rubra Pease. 



The status of Agatha virgo A. Adams 1860, [Menestho, 1861, Myonia, 1861, Amathis 

 1861], is not known to us. From the meager description we are inclined to believe 

 that it is allied to Actaeopyramis Fischer. 



