1-2 



whorl two thirds the length of the shell ; slightly angular at peri- 

 phery ; suture delicate. Aperture ovate, rounded at base ; lip 

 slightly everted, with a constriction behind it ; spiral fold on the 

 columella nearly transverse, elevated, sharp-edged, and a small 

 umbilical opening is seen running under it. 



Length one fourth of an inch ; diameter one tenth of an inch. 



Inhabits Santa Barbara. Col. Jewett. 



Has most of the characters of 0. conoidea of Europe, but is per- 

 haps proportionally broader. 



ODOSTOMIA ACHATES (PL XIV. Fig. 13.) 



T. ovato-lanceolata, nitida, longitudinaliter striata, albida, maculis elongatis, 

 rubiginosis obscure zonata ; spira acuta, anfr. ad 9 vix convexis, ultimo dirni- 

 diam longitudinis adequante, basi rotundata et strict unicA submediana cinctA ; 

 apertura angusta, ovata, postice acuta ; columella plied mediana et duabus 

 minoribus anterioribus instructa. 



Shell ovate lanceolate, shining, with distinct and rather distant 

 longitudinal stria? ; color, whitish near the suture and mottled with 

 pale rust color, arranged somewhat in bands of elongated spots ; spire 

 acute, more rapidly tapering at tip; whorls eight or nine, scarcely 

 convex, of which the last is half the length of the shell, entire and 

 rounded at base, having a single impressed line around the middle, 

 which runs up two or three whorls just behind the suture. Aper- 

 ture narrow ovate, rounded in front, acute behind ; lip acute ; colu- 

 mella with a very obvious fold at the middle, and two much smaller 

 ones between it and the base. 



Length half an inch ; breadth three twentieths of an inch. 



Inhabits Mazatlan. Col. Jewett. 



At first sight this would be taken for a land shell, like some of 

 the slender and polished Achatinella. Its generic place is some- 

 what doubtful. It has not only the single fold of Monotigma and 

 Odostomia, but at least two others like Pyramidella. It will some 

 day be regarded as a distinct genus. 



FUSUS AMBUSTUS (PI. XIV. Fig. 18.) 



T. fusiformis, subequilateralis, dilute rufa, fusco tincta ; spira elongata, acuta, 

 anfract. ad octo convexis, subangulatis, liris crebris cinctis, et plicis conspicuis 

 ad octo ornatis, prope suturam constrictis j apertura parva ; rostro subrecto. 



Shell fusiform, its largest diameter near the middle ; color yel- 



