ZONITES. 



2S1 



Subfamily ZOXITIX.E. 



Body more or les.s spiral, prominent from the middle of 

 the upper part of the foot, and covered with a more or less 

 developed spiral shell, sometimes hidden by the reflexed 

 edge of the mantle. Subcaudal gland linear, perpendicular. 



The Zonit in se correspond to the Sienojyidas of II. & A. Adams. 

 There are numerous genera found in every quarter of "the globe, 

 but represented in North America hy Zonites alone. 



502. 



ZOXITES, MoxTF. 



Shell broadly umbilicated, orbiculate, convex or discoidal, 

 striated or decussated, beneath smooth and shining ; whirls 6 or 

 T, gradually increasing in size; aperture oblique and lunate; 

 peristome straight, acute, and slightly thickened 

 internally. 



Animal with a caudal mucus pore. 



Jaw arcuate, large, simple, concave margin with J:i\y o( Zjiiues 



, . . , . fuliginosa. 



a strong median projection. 



Lingual membrane broad, teeth long and slender, centrals tri- 

 cuspid, laterals bicuspid, uncini aculeate, curved. The central 



Fig. 503. 



Lingual dvuiitiou ot Zonites faUgiiusa. 



