ODOSTOMIA. 325 



Odostomia producta. 



Fig. 175. 



Shell small, conio-cylindrical ; whorls eight, nearly flat; epidermis light brown; 

 colinuella llexuous. 



Jaminia proihwla, Adams, Bost. Journ. Nat. Hist. iii. pi. 3, fig. 8. 



Cltpmnitzia producta, Stimpson, Shells of New England, 41. 



Odostomia producta, Gould, Inv. 1st cJ. 270, fig. 175. — Stimpson, Check Lists, 5. 



Shell small, elongated, conic-cylindrical, very slender, composed 

 of eight or more flattish whorls, separated by a well-impressed sut- 

 ure ; tip blunted, as if one or more whorls were removed ; 

 surface faintly marked by lines of growth, and covered ^'°' ^^^' 

 with a dusky, horn-colored ei)idermis ; occasionally an in- 

 distinct revolving line may be seen on two or three of the 

 lowest whorls ; aperture about one fourth the length of the 

 shell, ovate, regularly rounded in front, the pillar margin '^■p[^^'"'- 

 modified by the rising and revolving of the outer lip around 

 it, so as to produce a partial fold. Umbilicus none. Operculum 

 thin, horny, spiral, apex at one side. Length, one fourth of an 

 inch ; breadth, one fifteenth of an inch ; divergence, twelve degrees. 



Found by Professor Adams, in September, 1839, near high-water 

 mark, in a cove on the east side of Fairhaven. 



It is distinguished from O. bisuturalis by the same characters as 

 O.fusca is. To this last it is very closely allied ; and, as neither of 

 them has any very prominent peculiarities, it may not be possible 

 to make a})parent in words distinctions which are quite obvious to 

 the eye. This is, however, a much more slender shell than O. fus- 

 ca, has one or more additional whorls, a much lighter colored epi- 

 dermis, less convex whorls, and no approach to an umbilicus. 

 While the two shells are about equal in length, the lower whorl of 

 O. producta is not more than two thirds as large as that of O.fusca, 

 so that it has a very much more slender and cylindrical form ; and 

 this it is which most readily strikes the eye on comparison. 



This does not belong to the genus Jaminia of Leach ; and Brown 

 has given us no characters for the genus, as he employs it. 



Odostomia fusca. 



Fig. 176. 



Shell small, elevated-conical, rather blunt at tip, and sub-umbilicated ; color 

 dark brown ; aperture broadly ovate. 



