﻿380 DESCRIPTIONS OF NEW SPECIES OF 



linear, canal straight, not emarginate anterior^, posterior sinus shallow and situated 

 a little distance from the suture, outer lip thin on the edge and crenate within, inner 

 lip thin and marked by numerous bead-like teeth, seen only in the adult shell ; surface 

 marked like Pleurotoma. 



Observation. — The most prominent character by far is the peculiar arrangement of 

 the inner lip. The markings are not folds encircling the columella as in the well 

 known genus Voluta, and in the following genus, but a row of minute beads which are 

 found only in the adult individual. I have before me numerous immature specimens 

 which show no trace of these beads or papillge. 



i^E. KETiciTLATA. PL 67, fig. 18. Subscalariform, whorls eight, apex acuminate, 

 mouth narrow, linear, outer lip thin on the edge, behind thickened and strongly den- 

 tate, inner lip beaded or toothed nearly the whole length, canal straight; surface of 

 the first four whorls smooth and polished, of the fifth marked by minute longitudinal 

 ribs, the remainder by revolving lines between which, but not extending over them ; 

 are numerous impressed longitudinal lines, giving under the glass a cancellated 

 appearance. 



Dimensions. — Length "45 in., length of mouth '22 in., w ; idth of body whorl "13 ir. 



Collections of the Academy and Smithsonian Institution and my collection. 



SCOBINELLA, Con., 1848. 



4— S. ceassiplicata. PI. 67, fig. 19. Fusiform, robust ; spire straight on the sides ; 

 mouth about half the length of the shell, canal straight; umbilicus rudimentary; 

 surface marked by revolving ribs, one narrow nodose rib at the top of the whorl, one 

 wider nodose rib sometimes double on the shoulder, and numerous smaller plain ribs 

 crossing the remainder of the whorl and alternating in size; the nodes on the first 

 two ribs, which are somewhat wider than exhibited on the figure, give this shell a' 

 strongly cancellated appearance to the naked eye. 



Dimensions. — Length -3 in., length of mouth -16 in., width of body whorl -.13 in. 



' - S. laeviplicata. PI. 67, fig. 20. Thick, fusiform ; whorls eight or nine, carinate ; 

 apex acuminate ; mouth narrow, canal short, outer lip striate within, corresponding 

 with the external ribs, inner lip thickened, the folds on the columella smaller than in 

 the preceding species ; surface marked by twelve or fifteen angular revolving striae ; 

 no traces of longitudinal ribs or nodes, but obsolete lines of growth. 



Dimensions. — Length "22 in., length of mouth - 08 in., width of body whorl "08 in. 



Collection of the Smithsonian Institution. 



DISTORTIO, Bolton. 



--J D. septemdentata. PI. 67, fig. 21. Short, robust; whorls eight, spire short, 

 acuminate ; mouth patulous, outer lip thin on the edge, thickened behind the edge 



