GENERA OF SHELLS. 89 



This shell was foniiarly placed with the patellœ ; 

 but on account of the notch at the lower part of the 

 aperture, and from its having an opercukiin, it differs 

 materially. 



C. Peruvianas.' 



Harpa. Shell oval, more or less inflated, 

 having parallel, longitudinal, inclined, com- 

 pressed and acute ribs. Aperture emarginated 

 inferiorly ; without a canal. Spire short. 

 Columella smooth, flattened, and pointed at 

 base. 



H. imperially, ventricosa, conoidalis, nobilis, articularis, 

 rosea, minor, striata, inutica. 



DoLUTM. Shell thin, ventricose, inflated, 

 generally subglobular, rarely oblong, trans- 

 versely banded. Lip dentate or crenulate 

 throughout. Aperture oblong, emarginate in- 

 feriorly. 



The dolium is distinguished from the harpa, terebra, 

 eburna, &c. by having no longitudinal ribs, by their in- 

 flated, ventricose, subglobular form, the spire being- 

 much shorter than the lov/er whorl, whence the aper- 

 ture is very large, and occupies more than two thirds 

 the length of the shell. They are thin, and attain a 

 large size. They are all encircled by transverse Lands, 

 which render the margin of the lip crenate throughout. 



D. galea, oleaViuiii, maculatum, fasciatum, pouium, varie- 

 gatum, perdix. 



BucciNUM. Shell ovate or ovate-conic. 

 Aperture longitudinal, having at base a notch, 



