ODOSTOMIA. 267 



(S. H.) ; and has been met with on most of the investi- 

 gated portions of the British coast. 



Some six years ago, when few cabinets could boast of 

 more than three or four species of Odostomia, and the data 

 for determining the limits of species were consequently 

 circumscribed, Mr. Hanley gave the name of iurrita (Zool. 

 Proc. 1844, p. 18. — Brit. Marine Conch, p. xxxvi. 

 f. 10) to a remarkably elongated individual of this genus, 

 which was taken in the islet of Herm, near Guernsey. The 

 individual described from was worn, broken-mouthed, and 

 a little distorted, but still exhibited a form very diiferent 

 from that of any known Odostomia. The shell we now 

 figure (plate XCV., fig. 9) is precisely identical, except 

 that the whorls are more regularly coiled ; it approaches 

 so closely to the produced and subcylindraceous variety of 

 unidentata^ that, until the examination of the animal shall 

 manifest its true rank in the genus, we think it better to 

 esteem it a provisional variety of the present species. The 

 shape, however, tapers more acutely, the short body is well 

 rounded below, and the whorls, of which there are five and 

 a half (the nucleus is large) are rather higher, much more 

 convex (especially anteriorly), and rather more oblique. 

 The microscopic spiral striulse that are often distinguish- 

 able in unidentata are in certain individuals of this form 

 more perceptible than usual. 



O. sTRioLATA, Alder. 



Conic ; whorls a little convex ; spirally striolate ; body sub- 

 angulated ; throat smooth ; fold strong ; no umbilicus. 



Plate XCV. fig. S. 



Under this name Mr. Alder has forwarded to us a single 

 individual, worn indeed and imperfect, but nevertheless 



