250 EMARGINULA. 



E. elongata Costa. P!. 64, figs. 12, 13. 



Shell small, elliptical, its altitude contained 21 times in its 

 length ; front slope strongly arched, back slope short, steep, straight, 

 less than one-fourth as long as the front slope. Apex strongly re- 

 curved, near the posterior end. Sculpture consisting of a lattice- 

 work composed of strong, subequal or alternately smaller radiating 

 ribs crossed by elevated concentric threads ; radiating riblets 32-36 

 in number about 20 of them reaching to the apex. Interstices and 

 pits between the ribs having regularly placed microscopic white 

 dots of an elongated form, about 6 of them in each pit. 



Inside white, with opaque white dots showing through. No cal- 

 lus in front, but a slight sulcus ending in the narrow slit in front, 

 the latter a little less than one-fourth the length of the shell. 



Length 9, breadth 6, alt. 33 mill. 



Mediterranean and Adriatic Seas ; Atlantic Ocean at the Canaries, 

 etc. 



E. elongata Costa, Oss. Zool. Is. Pantelleria, p. 10, no. 17, 1829. — 

 Phil. Einira. i, p. 115, t. 7, f. 13.— Buq,, Dautz., & Dollf., Moll. 

 du Rouss. p. 451, t. 54, f. 9-12. 



A white, semitransparent little shell, more elevated than E. huz- 

 ardi, more depressed than cancellata, fissura or solidula. The ribs 

 are comparatively few, and the lattice-work coarse. 



E. compressa Cantraine. 



I have not access to the description and figures of this species. 

 Jeffreys say that it differs from E. papillosa in being more compressed 

 at the sides, and is shorter or has a rounded and more globular out- 

 line ; it is readily distinguishable from E. elongata by the shape and 

 much finer sculpture. The distribution given by Dall is : 



Off Portugal ; Georgia, Florida Strait to Barbados, 84-630 fms. 



E. compressa Cantraine, Diagn. esp. nouv. Moll. (Bull, de l'Acad. 

 roy. Brux. ix, 12, 1835), p. 22.— Jeffreys, P. Z. S. 1882, p. 679.— 

 Dale, < Blake ' Gastrop., p. 406 ; Catal. Mar. Moll. S.-E. U. S., p. 

 170. — E. tuberculosa Libassi, Mem. Conch, foss. Palermo (Atti, iiL 

 1859), p. 15, f. 1. 



E. papillosa Risso. PI. 64, fig. 1. 



Shell sculptured with unequal, alternately wide and narrow radi- 

 ating papillose ribs ; interstices ornamented with delicate scales ; 

 apex subdepressed ; epidermis gray. Length 12 mill. (Risso.) 



Mediterranean and Adriatic Seas, 10-40 fms.; Atlantic, off W. 

 Europe. 



