MOLLTJSCA OF THE ' CHALLENGER ' EXPEDITION. 427 



the sinus-area, and is occupied by the dislocated tops of the ribs ; 

 these become on the upper whorls more and more a slightly pro- 

 minent tubercled string-course below the suture ; this band is 

 cut off by a slight furrow from the true top of the ribs, which 

 project here a little angularly, The whole surface is closely 

 beset with spiral threads and furrows ; of these threads that at 

 the suture is broadish but depressed ; below it is another stronger. 

 On the body and base are about ten accompanied by one or some- 

 times two very small ones. The furrows are broadish, square, and 

 flat in the bottom ; on the snout are three or four ; and on the 

 twisted cord in front there are five. Colour : a narrow band 

 above the suture and the sinus-area below are of a deep rich buff, 

 which extends to the whole base, intensifying to a rich ruddy 

 orange on the snout and pillar; the ribs are white, but except 

 on the snout their interstices are dark purply brown. Spire 

 very regularly conical and high. Apex consists of about 2\ very 

 small, conically tapering, embryonic whorls, parted by a very fine 

 suture, and rising to a minute rounded tip, which is very much 

 bent down on one side. Whorls 13 in all, conical, barely convex, 

 and hardly angulated near the top ; they are short and broad, 

 of very regular slow increase ; the last is small, and contracts 

 quickly but not deeply, with a rounded base prolonged to a 

 broad conical snout which is obliquely cut off in front, with 

 a twist, which forms a sort of slight cord across the point. 

 Suture slightly impressed, distinct. Mouth small, narrow, pear- 

 • shaped, rather sharply pointed above, with a longish, curved, 

 rather narrow, and open canal in front, which runs down the 

 massive snout, and is patulous, till at the very point the edge is 

 slightly inverted. Outer lip broken : the sinus lies about -£$ of 

 an inch below the suture, from which it is separated by a strong 

 shelf of that breadth and about j 1 ^ inch long ; it is deep, rounded, 

 and narrow, being shut in by the high shoulder into which the 

 outer lip projects below it ; orange-coloured, through which the 

 dark bars shine. Inner lip : there is a small but thick and nar- 

 row pad above ; below, it is reverted on the pillar, and has a 

 raised edge ; in front it is not bent back again, but runs down 

 to the point with a prominent sharp edge : the pillar is rather 

 short, strong, not broad, conical, sharp-pointed, not twisted, and 

 not cut off obliquely, as usual, from the right of the shell 

 towards the left, but, on the contrary, from the left to the right; 

 and here the projection of the lip-edge leaves a small, shallow 



