14 Datt and JBartsch The Pyramidellidce. 



Peritreme not continuous, aperture not 

 rissoid 



Subg. Liostomta $. Sars., 1878. 

 Type, Rissoella? eburnea 



Stimpson. 



B 2 Varices present 



Shell smooth, axial sculpture indicated by a few varices, spiral 

 sculpture wanting 



Subg. Oceanida De Folin, 1870. 



Type, Oceanida gradata De Fol. 



A 2 Early postnuclear whorls sculptured differently from the later ones 

 Early post nuclear whorls loosely coiled, plain; later ones closely 

 . coiled with a spiral keel at the periphery and one at the summit 

 of the whorls; base spirally lirate 



Lysacme subg. nov. 



Type, Chryxallida dausiliformis Cpr. 



Early post nuclear whorls axially ribbed, succeeded by one or 

 two strongly spirally and faintly axially lirate whorls; the rest 

 of the whorls are marked by a reticulated sculpture consist 

 ing of raised axial and spiral cords 



Subg. Obtortio Hedley, 1899. 



Type, Rissoa pyrrhacme Melville 



and Standen, 1899. 



DESCRIPTIONS OF NEW SPECIES THAT ARE TYPES OF 

 SUBGENERA DEFINED IN FOREGOING SYNOPSIS. 



Pyramidella (Sulcorinella) dodona sp. nov. 



Shell small, elongate-conic, milk-white. Nuclear whorls one and one- 

 half, smooth, obliquely immersed in the first postnuclear whorl. Post- 

 nuclear whorls flattened, moderately shouldered at the summit, having 

 a strong spiral sulcus at the periphery. Base of the last whorl well 

 rounded and strongly umbilicated. The summits of the whorls fall a 

 little anterior to the peripheral sulcus of the preceding whorl and cause 

 the part of this, exposed between the sulcus and the summit of the 

 next whorl, to appear as a narrow raised spiral band. Entire-surface of 

 the shell crossed by many axial lines of growth and numerous subequal- 

 ly and closely spaced spiral striations. Sutures subchannelled. Aper 

 ture ovate, posterior angle obtuse, outer lip thin, columella somewhat 

 curved and reflected having a strong oblique fold a little anterior to its 

 insertion; parietal wall covered by a thin callus. 



