136 AMERICAN JOURNAL 



resemblance in general form to Vivipara, from which, however, 

 the plicated columella and other characters at once distinguish it. 

 I take pleasure in dedicating it to Dr. Palmer, to whose 

 unwearied exertions are due many rich additions to the National 

 Museum. 



act^eonid^e. 



ACTiEON, Montfort. 



Actceon, Montf., Conchyl. Syst. ii, p. 315, 1810. 



Characters. — Aperture rounded, entire. A single plait on the 

 columella. Shell imperforate, with an elevated spire. 



Type A. tornatilis, Gmelin. 



Subgenus Rictaxis, Dall. 



Shell like Actceon, but with the columella projecting beyond 

 the line of the anterior margin, forming a small tooth- like pro- 

 jection, or truncate obliquely. 



Type Rictaxis puncto-coslata. 



Tornatella puncto-coslata, Cpr., Suppl. Rep. 1863, p. 646. 



Habitat, Catalina Island and San Diego, Cal., Cooper ; Mon- 

 terey, Dall. 



This species, distinguished by its peculiar columella, which 

 removes it from Action, is not uncommon, dead, on the beach 

 at Monterey, and adhering to the tentaculre of the immense 

 Actinias on the rocks at that locality, a position where many 

 small and interesting shells were obtained by me among the 

 small stones and fragments with which these creatures cover 

 themselves. It presents some resemblance to Bullina, from 

 which the columellar plait and imperforate axis distinguish it. 



TORNATINA, A. Adams. 



Tornatina harpa, n. s. (Dall, MSS. 1866.) 



Shell small, white, of four and a half whorls ; tabulate and 

 sharply carinate above, characterized by sharp grooves and 

 raised lines, parallel with the lines of growth, which extend half 

 over the whorls and become obsolete anteriorly. Apex mam- 

 millated, minute, globular, prominent, suture canaliculated. 

 Anterior portion of the last whorl smooth. Last whorl slightly 

 narrower above. Aperture long, narrow, effuse below, with a deep 

 narrow sinus at the suture. Columella thickened with a thin 

 layer of white callus. Columellar plait obsolete in the adult, 



