MITRELLA. 123 



whorls 6, flattish or scarcely convex, smooth, separated by a deep 

 suture, giving the spire a slightly turreted aspect ; last whorl 

 feebly angular at the middle, contracted inferioiiy, and striated 

 around the extremity ; aperture pale lilac within, occupying about 

 three-sevenths of the entire length ; outer lip arcuate, thickened, 

 especially at the upper part ; thin at the margin, and armed 

 within the mouth with about 7 elongated tubercles ; columella 

 arched above, oblique at the base, with indications of one or two 

 tubercles below the middle, covered with a thin whitish callosity ; 

 basal canal a little recurved. 



L. 14, cliam. 5'33 mill. ; aperture 6 long, 2*5 broad. 



Vancouver's Island. 



This species is broader than C. cribraria, has a less acuminated 

 and more turreted spire, and the color is much paler ; the outer 

 lip, too, does not exhibit nearly so distinct a superior sinus and 

 the last whorl is more contracted at the base, forming more of 

 a distinct basal canal with the lower extremity of the- labrum. 



The above is the full description of this unflgured species. 

 The distinctive characters from C. cribraria do not appear to be 

 very well marked, and the habitat given perhaps needs verifi- 

 cation. 



C. D^DALA, H. Adams. 



Shell narrow, elongate ; pallid luteous, reticulated with chestnut 

 and maculated with the same color at the suture ; outer lip sinuated 

 behind, not dentate. Length, 5 mill. 



New Hebrides. 



I have not seen this species ; the description much resembles a 

 small, well-covered C. cribraria. 



C. OBLITA, Reeve. PI. 48, fig. 78. 



Shell minutely spirally striated throughout ; transparent white, 

 with longitudinal orange-brown streaks ; aperture small, the colu- 

 mella excavated, the outer lip simple. Length, 8 mill. 



Peru. 

 C. VELATA, Reeve. PI. 48, fig. 79. 



Shell ovate, smooth, shining; very densely reticulated with 

 chestnut, whorls rather flattened ; aperture small, lip denticulated 

 within, slightly siuuated at the upper part. 



Habitat unknown. 



