FAMILY TROCHIDJS — JANTHINA. 125 



Janthina FRAGILIS. 



PLATE XXXVI. FIG. 3G0. 



Janthina fragilis. Brug. Encyrloped. Melhodique, pi. 45G, fig. 1. 

 J. id. Gould, Invertebrata of Mass. p. 240. 



Description. Shell globose-conic, with a short spire. Body-whorl large, angulated in the 

 middle : surface shining, with incremental wrinkled lines, and with revolving lines beneath 

 the angle ; aperture large, semioval ; lip retiring as it passes the angle of the whorl ; pillar- 

 lip straight. 



Colo?: Deep violet beneath the angle ; lighter above. 



Length, 0'8. Width, l'O. 



This shell is never found on our shores, unless driven by heavy storms. In the autumn of 

 1839, according to Dr. Gould, great numbers were thus thrown upon the shores of Nantucket. 



GENUS SCALARIA. Lamarck. 



Animal furnished with a proboscis, with two tentacles ending in filaments, and with the eyes 

 on an external tubercle. Foot short and oval ; the male organ very slender. Marine. 

 Shell turreted, elongated ; whorls rounded, with longitudinal subacute elevated ribs ; aper- 

 ture rounded, the margin reflected, continuous. Opercle horny, thin, paucispiral. 



Obs. The animal of this genus is yet incompletely known. We are chiefly indebted to 

 Messrs. Say and Couthouy for our knowledge of the American species. 



SCALARIA SUBULATA. 



PLATE VI. FIG. 124. A. b. 



(STATE COLLECTION.) 



Scalaria sutmlata. Couthouy, Bost. Joura. Nat. Hist. Vol. 2, p. 94, pi. 3, fig. 4. 

 S. id. Rossell, Essex Joum. Nat. Hist. Vol. 1, p. 75. 



S. granlandica. Gould, Invertebrata of Mass. p. 219, fig. 170. 



Description. Shell tapering to a fine point, imperforate. Whorls nine or ten, contiguous, 

 slightly convex, with eight to fifteen stout compressed oblique ribs, with intervening coarse 

 rounded vertical ridges, and seven or eight revolving stria? ; the ribs not ending abruptly at 

 the suture, but flowing along the sutural region to the preceding ones. Aperture nearly cir- 

 cular, bordered by a rib which is emarginate at the base. Opercle horny, shining. 



Color. Dull bluish white to livid brown ; lip and ribs white. Animal yellowish grey, with 

 whitish spots ; mouth rather large, rounded, corrugated. 



Length, 1  0. Width, 0-35. 



