264 REV. R. BOOG WATSON ON THE 



slightly levelled back. Operculum is membranaceous, thin, with 

 a distinct and slightly impressed suture, and scored with sharp 

 radiating lines. H. 0"64. B. 053. Penultimate whorl, height 

 0-15. Mouth, height 0-49, breadth 047. 



N. glooosa, King, from the Straits of Magellan, is somewhat 

 like this, but has a much more depressed spire and longer mouth. 

 Prof. v. Martens was good enough to compare this species for me 

 with his N. grisea, and from that he says " it differs (1) by being 

 considerably larger, (2) thinner, (3) penultimate whorl less pro- 

 minent, (4) the last whorl, when seen from the dorsal side, is 

 higher or longer relatively to the breadth, (5) the umbilicus is 

 narrower ; I think, therefore, that it is a distinct species, and I see 

 also no other in the Berlin collection which might be identical." 



10. NaTICA FARTILIS, 11. Sp. 



St. 145. Dec. 27, 1873. Lat. 46° 43' S., long. 38° 4' 30" E. 

 Between Marion Island and Prince Edward Island. 50-150 fms. 

 Grey sand. 



St. 149 d. Jan. 19, 1874. Lat. 49° 32' S., long. 70° E. Bal- 

 four Bay, Boyal Sound, Kerguelen. 60 fms. Mud. 



St. 150. Feb. 2, 1874. Lat. 52° 4' S., long. 71° 22' E. Between 

 Kerguelen and Heard Island. 150 fms. Eock. Bottom tem- 

 perature 35 0, 2. 



Shell. — Globose, with a rather high spire and a somewhat 

 elongated and pointed base, thin, with a delicate light-green epi- 

 dermis ; umbilicus closed. Sculpture. Longitudinals — the lines 

 of growth are fine, hair-like, close-set strise. Spirals — the sur- 

 face is somewhat distinctly, though finely, scored with shallow 

 furrows and faint lines, which are microscopically crimped ; below 

 the suture the whorls are compressed by a broad very shallow 

 furrow, the lower side of which is very doubtfully angulated. 

 Colour porcellanous white under the delicate, slightly glossy 

 epidermis, which is pale green, streaked on the lines of growth 

 with darker green ; the umbilical pad, pillar, and inside are dead 

 white. Epidermis is a thin, rather persistent smooth membrane. 

 Spire is rather high and conical. Apex rather large, raised so 

 that the extreme tip projects, but rounded though not flattened. 

 Whorls 6 (of which the first 1| are embryonic) ; they are scarcely 

 rounded between one suture and the next, with a slight and 

 narrow margin below the suture, then very slightly compressed ; 

 the last is very large and tumid in proportion to the rest, which 

 project very little above it ; they are of slow and very regular 



