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GASTEROPODA. 



GENUS STROPHOSTYLUS (Hall). 



Strophostylus cyclostomus (Hall). 



Shell subglobose or transversely broad oval ; spire moder- 

 ately elevated ; volutions about four, rounded, the last 

 extremely ventricose and very much extended on the 

 upper side and at the sutural margin. Aperture circular 

 or subeircular, very oblique to the axis ; peristome thin, 

 entire, without sinus or emargination, spreading over the 

 surface of the next volution, rarely leaving a slight un- 

 bilicus. Columella lip grooved in the lower part, with 

 a rather strong spiral fold about one third the diameter 

 from the lower side of the aperture. Suture not canali- 

 culate. 



Surface marked by strong, crowded, lamellose striae of 

 growth parallel to the margin of the aperture, and by much 

 finer revolving, undulating lines, producing a finely cancel- 

 late structure in well preserved specimens. 



This species differs from any other described (except 

 S. elegans of the lower Helderberg Group) in the elevation 

 of the spire. From that it differs in being more ventricose 

 and more oblique. 



CRUSTACEA. 



GENUS DALMANIA (Emmerich). 



Dalmania verrucosa (Hall). 



General form elongate ovate, the greatest breadth across 

 the posterior part of the cephalic shield. Head semi- 

 circular, or, including the lateral spines which reach 

 to the base of the fifth thoracic segment, broad crescenti- 



