, PLEUROTOMA. 390 



Bergen to Spitzbergen in one hemisphere, and from 

 Cape Cod to Greenland in the other. This species differs 

 from P. rufa in having a longer body-whorl, a smaller 

 and more abruptly tapering (but not turreted) spire, an 

 oblique and shallow suture, and slighter ribs. It is the 

 Fusus pleurotomarius of Couthouy, and Defrancia VaJilii 

 of Beck in Moller's Index. 



11. P. TURRi'dTLA*, Montagu. 



Murex turricula, Mont. Test. Br. (i.) p. 262, t. 9. f. 1. Mangelia turri- 

 cula, F. & H. iii. p. 450, pi. cxi. f. 7, 8, and (animal) pi. TT. f. 2. 



Body creanicolour, faintly suffused with brown, and some- 

 times closely covered with very minute chalk-white specks : 

 head small and thick : pallial tube cylindrical and very long, 

 sometimes projecting in front like a horn : tentacles cylindrical, 

 extremely short above the eyes, with blunt tips : eyes small, 

 placed on the extremities of stalks which are nearly three- 

 fourths of the length of the tentacles and are annexed to (but 

 not amalgamated with) them, giving to this part of the ani- 

 mal the shape of an elongated and irregular cone : foot large 

 and broad, truncated or bilobed in front, with small angular 

 corners, and bluntly pointed or rounded behind : [odontophore, 

 pleural spine straight, with a conical head and the side exca- 

 vated and open. (Loven.)] 



Shell oblong-fusiform, rather solid, semitransparent, and 

 lustreless : sculpture, strong, sharp, and narrow, but not very 

 prominent longitudinal ribs ; these are angular on the top of 

 each whorl, curved on the body-whorl, and nearly straight on 

 that portion of the other whorls which lies below the suturai 

 ledge or step ; they extend to the suture and mouth, but not 

 to the base ; each of the last five whorls has from 12 to 15 

 ribs, the next has more, and on the preceding whorl they 

 become fine and close-set striae and are separated by the 

 stronger spiral striae ; they disappear towards the apex ; the 

 ribs are much narrower than their interstices ; the whole 

 surface (except the apex, which is quite smooth and glossy) is 

 thickly covered with fine, and usually equal-sized, spiral striae 

 (with frequently slighter intermediate stria?), which are more 



* A turret. 



