MOLLUSCA OE THE ' CHALLENGER ' EXPEDITION. 269 



parted above, they are slightly more crowded on the base ; the 

 2nd, 3rd, and 4th feebly carinate the body-whorl ; between them 

 lie 3 or 4 slighter rounded threads, which do not form tubercles 

 on the ribs ; below these on the base are 6 other spirals, with a 

 similar feebler spiral between them, while on the snout there 

 are about 9 pretty equal, close-set, rounded threads which run 

 parallel with the open slit of the canal. Colour porcellanous 

 white, with chestnut on the larger spiral threads. Epidermis of 

 a pale ruddy brown, thin, rising along all the spirals into distinct 

 short, sharp bristles, which are set on small round tubercles. 

 Spire high and rather narrow, scalar, conical, but with its profile 

 lines broken by the contracted suture. Apex consists of four 

 polished, but spirally threaded, white, turbinated whorls, of which 

 the first is extremely small and somewhat immersed. Whorls 

 8-9 in all ; they have a sloping flat shoulder to the second spiral, 

 ; below which they are cylindrical and scarcely convex ; the 

 last whorl is more tumid and rounded than the others, but 

 is very much and rapidly contracted to the rather small, 

 longish, sharply conical, lop-sided, and reverted snout, which, 

 viewed from above, projects to the left from the right side 

 of the base. Suture interrupted by the ribs and scarcely at 

 all impressed, but strongly defined by the long sloping shoulder 

 below it ; on the embryonic whorls it is slightly channelled. 

 Mouth almost round, but a little angulated and slightly distorted ; 

 along, straight, and very narrow slit of a canal runs out of it 

 toward the left, neither narrowing nor widening from the place 

 where it leaves the mouth ; its sinistral inclination seems to give 

 the whole snout a turn to the left. Outer lip : its semicircular 

 curve is a little flattened ; at the point of the mouth it turns 

 quickly and runs quite straight to the point of the snout, where 

 it is a little obliquely cut off; the edge is sharpish, but with a 

 tendency round the mouth to become double, in the form of an 

 outside and an inside lamella parted by a minute shallow furrow ; 

 it is thickened outside by the slightly remote, narrowish, rounded, 

 almost scrobiculated * varix, which on the snout loses definiteness 

 and becomes doubtful ; within it is thickened by a strong porcel- 

 lanous milky-white varix, on which project 6 to 8 tubercle-like 

 teeth, which are slightly elongated from within outwards; this 



* I use this word to recall the similar, though stronger, feature in Banella 

 scrobiculator, L. 



