74 GENERA OF SHELLS. 



S. imbricata, rubra, sulcifera, auricula, planulata. 



Stomatia. Sliell earshaped, imperforate ; 

 spire prominent. Aperture entire, oblong, 

 ample ; lips equally raised. A transverse, 

 tuberculous rib along the back. 



Distinguished from haliotis by the dorsal rib bemg 

 imperforate. 



S. phymotis, obscurata. 



Haliotis. Shell earshaped, generally flat- 

 tened ; spire very short, sometimes depressed, 

 nearly lateral. Aperture very large, longer than 

 broad, entire in its perfect state. Disc per- 

 forated with holes disposed in a line parallel to 

 to the pillar lip, and near it, the last beginning 

 by a notch. 



H. Midoe, iris, tubifera, excavata, australis, tuberculata, 

 striata, asinina, glabra, lamellosa, unilateralis, rugosa, ca- 

 naliculjata, tricbstalis, dubia. 



PLICACEA. 



Aperture of the shell not effuse ; colmnella plaited. 

 Distinct from the auriculae by their general form and 

 projecting spire; and from voluta, mitra, &c. by 

 having no notch at the base of the aperture. 



ToRNATELLA. Shell couvolutc, ovatc cy- 

 lindrical, generally striated transversely, and 

 free from epidermis. Aperture oblong, entire ; 

 lip sharp. One or more folds on the columella. 



T. flammea, solidula, fasciata, auricula, nitidula, pedipes.' 



Pyramid ELLA. Shell turreted, destitute of 



