REPORT ON THE GASTEROPODA. 293 



sinus does not, as in Clathurella, lie quite at the upper angle of the mouth. The shell has some 

 resemblance to Pleurotoma nodi/era, Lam., from China and the Philippines ; but in that species the 

 body-whorl is much more tumid, the canal is much longer and is more bent to the left, the apex is 

 more uninterruptedly conical, the suture is deeper, the spiral threads are not so universal, and are in 

 their course regular. In texture this species is very much like Pleurotoma (Typhlomanyelia) nivalis, 

 Loven, but the length of its snout excludes it from the Tyjihloviangelia group. 



21. Pleurotoma (Surcula) syngenes, 1 Watson (PI. XX. fig. 2). , . 



Pleurotoma (Surcula) syngenes, Watson, Prelim. Report, pt. 8, Journ. Linn. Soc. Lond., vol. xv. p. 396. 



Station 23. March 15, 1873. Lat. 18° 24' N., long. 63° 28' W. Off Sombrero 

 Island, West Indies. 450 fathoms. Pteropod ooze. 



Station 24. March 25, 1873. Lat. 18° 38' 30" N., long. 65° 5' 30" W. Off Culebra 

 Island, West Indies. 390 fathoms. Pteropod ooze. 



Shell. — Long, narrow, biconically fusiform, sharply carinated and tubercled on the 

 keel, polished, thin, white. Sculpture: Longitudinals — there are very many, fine, close- 

 set, slightly raised flexuous lines of growth. Spirals — there is a sharp keel which lies 

 about §■ down the whorls ; it is very prominent from the concavity of the whorl above and 

 below ; the sharpness of this keel is due not so much to its crest, which is rounded, but to 

 its being beset by prominent round, conical, pointed tubercles, of which there are about 

 15 on the penultimate whorl ; on the upper whorls these are fewer, but they begin at once 

 on the first whorl below the embryonic shell ; on the last whorl they disappear entirely 

 toward the mouth. Besides the carina, there are many delicate lines ; three or four of 

 these, very fine, smooth, and flat, come in below the suture ; at about ■£$ inch below the 

 suture is a fine, sharp, engraved line ; about 6 more of these, but less strong, come in 

 above the keel. Below the keel the sculpture is somewhat similar, but less distinct and 

 less regular. On the snout the interstices rise into rounded, slightly roughened threads, 

 which on the extreme point become feebler. Colour ivory-white. Spire high, narrow, 

 conical, but with the profile-lines broken by the deep concave curves at the sutures. 

 Apex, the 2-| embryonic whorls are small, cylindrical, and bluntly rounded at the top, 

 which is slightly pressed down on one side. Whorls 11^, strongly angulated, with a 

 concave curve between the keels ; they are rather narrow and of very slow increase : the 

 last one is a little tumid, with a very regular convex curve, which contracts evenly to a 

 long, projecting, narrow, cylindrical snout, lying very nearly in the axis of the shell. 

 Suture a very faint, delicate, and regular line, well defined by the concavity of the whorl 

 both above and below it. Mouth club-shaped, but long and narrow, sharply pointed above, 

 and very much twisted in consequence of the great depth and width of the sinus. Outer 

 lip : originating markedly below the keel, it leaves the body at a very acute angle ; its 



. l evyyttrii, allied. 



