OP CONCHOLOGY. 



MONOGRAPH OF THE TERRESTRIAL MOLLUSCA OF THE 

 UNITED STATES. 



BY GEORGE W. TRYON, JR. 

 [Concluded from Yol. 3. page 324.] 



Family AURICULID^. 



Shell oval or oblong, generally of a dark brown or chocolate 

 color, with a more or less long and narrow aperture, the lip of 

 which is generally toothed within, not umbilicate ; not opercu- 

 late. 



Animal amphibious ; furnished with two tentacula, with eyes 

 at their bases. 



Remarks. Although air-breathers, these animals require a 

 large amount of moisture, and are generally found on the sea- 

 shore, in places covered by high tides. Both in the character of 

 the animal and in that of the shell, they much resemble the 

 fresh water pulmonifera, which they seem to connect with the 

 strictly terrestrial species. 



Sub-families. 



Auric ULIN.E. Shell ovate-oval, lip expanded or thickened. 



Animal terrestrial, extending inland. 



Melampinje. Shell oval or oblong, the outer lip thin, armed by 

 a submarginal row of teeth within. 



Animal inhabiting the sea-shore. 



