ODOSTOMIA. 143 



fine and close-set striae, which become stronger and more re- 

 mote on the base : colour whitish : spire long and tapering, 

 somewhat turreted ; nucleus partly exposed, and prominent, 

 twisted upwards in front, and sloping towards the back : whorls 

 5 (including the uppermost, from which the nucleus springs), 

 tumid, and very rapidly enlarging ; the last constitutes more 

 than two-thirds of the shell : suture deep and oblique : mouth 

 oblong or pear-shaped, narrow and contracted above, consi- 

 derably expanded or effuse below ; it exceeds in length two- 

 fifths of the whole spire : outer Up flexuous, retreating, and 

 sinuated at the upper corner of the mouth, where it is incurved 

 on the periphery : inner lip receding (almost concealed from 

 view), and remarkably thin on the upper part, thickened and 

 reflected, but not much curved, on the lower part ; it forms an 

 obtuse angle or point at the base : umbilicus none, or consist- 

 ing of an oblique depression, which sometimes ends in a small 

 chink : tooth, only a slight and obscure fold : operculum as in 

 the last species, but less strongly striated. L. 0-2. B. 0-075. 



Yar. Warreni. Smaller; having the basal strise more dis- 

 tinct, and the umbilicus more developed. Rissoa Warreni, 

 Thompson, in Ann. & Mag. N. H. xv. p. 315, pi. xix. f. 4. 

 0. Warrenii, F. & H. iii. p. 292, pi. xcvi. f. 2, 3. 



Habitat : Tynemouth (Alder) ^ west of Scotland 

 (Barlee), Aberdeenshire (Daw^son)^ Skye, Shetland, 

 Cork, Bantry, Caswell Bay near Swansea, Exmoiith, 

 Falmouth, Guernsey, and Herm (J. G. J.), Herm (Han- 

 ley), west of Ireland (Thompson, fide Alder), Helford 

 (Hockin) . Its foreign range appears to be, Loken in 

 South Sweden, 20 f. (Malm) ; and Etretat in Normandy, 

 at the same depth (J. G. J.). The variety has been 

 taken in Dublin Bay by the late Mr. T. W. Warren, on 

 the Turbot-bank oflP Larne, co. Antrim (Waller), Bir- 

 terbuy Bay, CO. Galw ay. Burrow Island near Kingsbridge, 

 and in rock-pools at Gwyllyn-vase near Falmouth (Bar- 

 lee), living at low-water mark at Budleigh Salterton 

 near Exmouth (Clark), Land's End and Falmouth 

 (Hockin). M. Mace found the variety at Cannes ; Mr. 

 Hanley dredged it at Villafranca, and I at Spezzia. 



