THE NAUTILUS. 75 



Type No. 50983 Walker Coll. Paratype in the Adams Col- 

 lection at Amherst College. 



I can not approximate this species to any that have been de- 

 scribed from the West Indies; several specimens were in the lot 

 received by Adams from Chitty mixed with the preceding 

 species. Compared with that, adamsi is smaller, more heavily 

 concentrically striate with growth lines, the apex is much more 

 obtuse, more elevated and scarcely at all eccentric. 



VI. 



The third form mentioned (1. c. p. 99) as occurring in the 

 Adams' "obscurus' from Jamaica consists of a number of 

 small specimens in both lots, which, at first, I thought repre- 

 sented a distinct species, but after carefully reviewing them 

 again I think it probable that they are young shells of the two 

 preceding species; at least, I do not feel like describing them as 

 distinct from the comparatively small series now available. 



VII. 



Ferrissia blandi n. sp. PI. Ill, figs. 10-12. 



?Ancylus obscurus Hald., Shuttleworth, Ann. Lye., N. H. 

 N. Y., VI, 1854, p. 72; Diag. Neuer Moll., No. 6, 1354, p. 99. 



Shell small, slightly elevated, broad oval, a little wider an- 

 teriorly, both ends broadly rounded; right lateral margin nearly 

 straight; left lateral margin somewhat more curved, especially 

 anteriorly; anterior slope nearly straight; posterior slope short 

 and slightly incurved; right lateral slope slightly concave; left 

 lateral slope a little convex; apex prominent, obtuse, slightly 

 turned toward the right side, situated at the posterior third of 

 the length and to the right of the median line, distinctly radi- 

 ally striate; surface smooth except for the fine, regular lines of 

 growth and traces of irregular rippling on the anterior slope; 

 light horn color. 



Length 2.75; width 1.8, alt. .8 mm. 



Type locality St. Vincent Island, West Indies. 



Type No. 50984 Coll. Walker. Paratypes in the Adams 

 Collection at Amherst College. 



The history of these specimens has already been given. This 



