36 • EEV. E. BOOG WATSON ON THE 



This species extremely resembles P. profundi, JefFr., especially 

 in the shape of the slit and apex and in the general style of 

 sculpture. In form, however, the "West-Indian species is lower, 

 and has the whole margin more spread out, so that while the 

 top of the cone is similar, the profiles of the slopes all round are 

 much more concave ; the radiating striae are muchi sparser ; tlie 

 tubercles on these are smaller and fewer ; the concentric striae 

 are much weaker and less continuous. The internal septum is a 

 little longer and more oblique, and is a little nearer the front, so 

 that the slit is more covered. The apex is so very like as to 

 make me doubt whether a fuller series of specimens might not 

 supply connecting-links between the two forms. And yet even 

 in the apex there are divergencies. Dr. Grwyn Jeffreys {I. c.) 

 says that F.profundi]idi% "the beak twisted to the left." The 

 tip is bent over to the left so as to lie obliquely on the posterior 

 slope ; but the minute embryonic apex lies toward the right hand 

 of the observer, the slit being in front. In the ' Challenger ' 

 species the apex is a very little larger, and the spire has about 

 I of a whorl more, the earlier rate of increase is slower, and the 

 extreme tip is not so much immersed and is a little more convex. 

 The texture of the shells, too, is different; and, finally, the six 

 ' Challenger ' specimens in all these respects agree with one 

 another. On the whole I believe the species to be distinct, but 

 they are certainly very closely allied. [I have now revised this 

 opinion, and united them.] 



8. PuNCTURELLA oxiA, n. sp. {o^vs, sharp.) 



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

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

 390 fms. Coral-mud. 



Shell. — Very small, thin, oval, narrowed in front, depressed ; 

 its slopes are straight at the sides, slightly and regularly convex 

 in front ; merely the extreme tip is curled in, and the top projects 

 sharply upwards and backw^ards immediately in front of the break 

 of the slit ; the surface is closely dotted with minute tubercles ; 

 the slit is rather large and round. Sculpture. There are neither 

 ribs nor concentric lines, but the surface is pretty closely dotted 

 over with minute rough tubercles, which are arranged in some- 

 what interrupted and irregular zigzags. Colour translucent, and 

 at the tubercles transparent. Apex incurved and turned back, but 

 not bent down ; there are 2 whorls. Slit : there is a largish 



