ODOSTOMIA. 261 



Odostomia plicata, Hanl. Brit. Marine Conch, p. xxxv. f. 13. — Seari.es 



Wood, Crag. Moll. pt. i. p. 85, pi. 9, f. 3 (fossil). 

 Turlonilla „ Loven, Index Moll. Scand. p. 19. 



Ododomia Eulimoides, Jeffreys (not Hanley), Ann. Nat. Hist. vol. xx. 

 (1847), p. 17. 



The numerous and regular eostellar lines, that spirally 

 adorn the throat of this solid Odostomia^ render the species, 

 despite of the variation of its shape — which is sometimes 

 broader sometimes narrower at the base — of easy recogni- 

 tion. It is of an uniform polished ivory-white, quite 

 smooth, and of a produced conical shape. The spire, 

 which rather quickly tapers to an acute point, is composed 

 of six very gradually increasing, rather short, and almost 

 flat volutions, the larger ones of which, for the most part, 

 abruptly slope in at their bases, which often gives a some- 

 what distorted appearance to the shell. The suture is 

 very profound or even canaliculated, and is moderately 

 slanting. The body scarcely occupies two-fifths of the 

 total length, and is abrupt, though rounded, at the basal 

 declination. The mouth, whose projection is but trifling, 

 is very decidedly shorter than the spire, has an oval-acute 

 figure, being gradually contracted at the upper extremity, 

 and is slightly disposed to effiision at the base or lower 

 end, which is well but not broadly rounded. The outer 

 lip is at first merely convex, and then gently arcuated. 

 There is a very strong fold in the middle of the inner lip ; 

 above it the outline is convex ; below it the pillar lip is 

 arcuated and reflected, but not appressed. The umbilicus 

 is wholly or partially concealed. Fine examples measure 

 nearly a quarter of an inch in length, and a tenth of an 

 inch in breadth. A variety exists, in which the whorls 

 are more rounded, and only five in number. The Medi- 

 terranean examples are, for the most part, more regularly 

 conical, and of rather faster vohitional increase. 



