168 SEMJNELLA. 



C. ATRAMENTARIA, Sowb. PL 56, figs. 98, 99; PL 43, fig. 27 ; 

 PL 57, fig. 1. 



Shell ventricose, with sharp-pointed spire, thick, closely 

 spirally grooved, longitudinally plicately ribbed, the ribs fading 

 towards the lower part; very dark chocolate, obscurely white 

 spotted ; aperture chocolate ; outer lip thickened at the margin 

 and dentate within. Length, 8'5-10 mill. 



Galapagos Islands; Gulf of Nicoya, Central America. 



C. lentiginosa, Hinds (t. 43, fig. 27), is synonymous and C. 

 pariolida, Duclos (fig. 1), is a specimen in which the longitudinal 

 plicae are not developed ; a not unusual form. 



C. NIGRICANS, Sowb. PL 57, fig. 2. 



Shell cancellated by longitudinal ribs and revolving striae, with 

 usually a single row of minute granules at the sutures ; aperture 

 rather small, lip thickened and denticulated within, conspicuously 

 notched behind ; dusky brown or nearly black, sometimes 

 obscurely lighter-banded on the middle of the body-whorl, and 

 frequently the sutural tubercles form a narrow white band. 



Length, 8 mill. 



Panama, Galapagos. 



C. PARVA, Sowb. PL 57, figs. 3-5. 



Minutely longitudinally ribbed, the interstices with fine 

 revolving striae ; yellowish brown, with a chestnut-colored supe- 

 rior band, and base. Length, 5-8 mill. 



West Coast Central America. 



The shell figured by Reeve (fig. 3) differs much from the type 

 and is apparently not adult. C. pamila, Duclos (fig. 5) appears 

 to be synonymous. 



C. SPADICEA, Philippi. PL 57, fig. 6. 



Cylindrically oblong, acuminated at the apex, longitudinally 

 ribbed, and decussated by faint revolving striae, slightly tuber- 

 culated at the sutures; dark chocolate, with a narrow white 

 band on the periphery, and sutural granules also whitish. 



Length, 9 mill. ' 



Mazatlan. 



A narrower shell than C. nigricans, with similar sculpture and 

 colors. 



