194 ON THE NAIADES, 



cies with which I am acquainted; but what eminently distinguishes 

 it is the subcoronate apex which, as far as we yet know, is peculiar to 

 this species. The body whorl nearly envelopes the superior ones. 

 When examined by the microscope, transverse striae are observed to 

 cause numerous minute depressions on its surface. 



Melanopsis princeps. Plate XIX. fig. 74. 



Testa acuto-elevatd, Imvi, rufo-fuscd, obsolete multimaculatd ; inferiori anfractu 

 carinato, dimidio basali transversim striata ; apice acuto ; anfractibus plus minus 

 quatuordeciin, planis ; aperturd quintd parte testas. 



Shell acutely elevated, smooth, transversely striate on the lower half of the body 

 whorl, which is carinate, reddish brown, with numerous indistinct spots ; apex acute ; 

 whorls about fourteen, flat aperture one-fiflh the length of the shell. 



Hab. Cape of Good Hope. 



My Cabinet. 

 Diam. -6, Length 2-1 inches. 



Remarks. — This is the most remarkable species of the genus which 

 I have examined. It differs from any described species in its great 

 elevation, in the flatness of its whorls, in its being covered with indis- 

 tinct spots, and in the absence of a large callus on the superior part of 

 the inner lip, as well also as in the great number of its whorls. The 

 spots are peculiar in being chain-like, alternately darker and lighter. 

 The operculum is horny, like that of the genus Melania. 



Melanopsis maculata. Plate XIX. fig. 75. 



Testd fusiformi, tenebroso-olivaced, intus fasciatd ; epidermide maculatd; an- 

 fractibus quaternis ; bast subtruncatd ; columella sine callo superno. 



Shell fusiform, dark olive, banded on the inside, and spotted in the epidermis ; 

 whorls four ; base but slightly truncate; columella not thickened above. 



