MOLLtrSCA OF THE * CHAIiLENGEB ' EXPEDITION. 37 



round hole obliquely cut off from tlie top, and prolonged bact- 

 ward.s into a point. Margin very thin, patulous, not crimped. 

 Inside glassy ; a very small hollow runs up into the apex ; the 

 surface is scored with many irregular, minute scratch-like white 

 threads, which are more perceptible on a slightly worn than on 

 a fresh specimen ; there is no anterior furrow : the slit, as seen 

 from within, is round, and is very little interfered with by the 

 short, thin, triangular, straight-edged, almost perpendicular 

 septum. L. 0-14. B. O'l. H. 007. 



This species has some features of resemblance to the last, but 

 is flatter and in sculpture is quite different. 



9. PUNCTTJEELLA SPOETELLA, n. sp. 



St. 24. March 25, 1873. Lat. 18°38'30",]SI"., long. 65° 5' 30""W. 

 Off St. Thomas, north of Culebra Island, Danish W. Indies. 

 390 fms. Coral-mud. 



Shell. — "Very small, strongish, oblong, with straight slopes 

 before and at the sides, and markedly concave behind ; the apex 

 is very small, and it alone projects backwards ; the surface is 

 finely cancellated ; the slit is lozenge-shaped. Sculpture. There 

 are very many slightly irregular, coarsish, radiating riblets crossed 

 by concentric threadlets, which are rather finer and closer but 

 somewhat more irregular, and which form minute knots in cross- 

 ing the riblets : from this sculpture results the basket-work 

 appearance from which the name of the species has been adopted. 

 Colour white, with a faint tinge of ruddiness. Apecc is exceed- 

 ingly minute ; and it is the little embryonic spiral alone which 

 projects, the entire number of whorls is only 1|. Slit roundish, 

 but acute in front, and (where closed by the septum) behind 

 drawn out into a sharp point so as to be lozenge-shaped when 

 viewed in its entire length. Margin straight on the sides, scarce 

 appreciably broader behind than before ; the edge is bevelled off 

 so as to be quite sharp. Inside glassy ; feebly marked with the 

 ribs which, as well as the concentric threads, shine through as 

 transparent ; the opening up into the apex is narrow and deep, 

 but not pointed ; there is no anterior furrow ; the slit, as seen 

 from within, is roundish pointed in front, and truncated behind 

 by the short, thin, triangular, straight-edged, little- oblique sep- 

 tum. L. 012. B. 0-08. H. 0-06. 



This beautiful species is not improbably full-grown, the very 

 small apex seeming to indicate that the species is in its own 



