KEPORT ON THE GASTEROPODA. 621 



thus formed are short and broad ; in the suture, but on its lower side, is a very small 

 sharpish threadlet, below which is a very short drooping shoulder without threads, but 

 scored by the riblets; round the extreme point of the base is a little shallow furrow, in cross- 

 ing which the riblets rise high and sharp ; beyond the furrow is a slightly swollen thread 

 scored by the riblets. Colour white. Spire high and narrow, and toward the apex drawn 

 out. Apex somewhat broken, but small, and composed of several smooth convex whorls. 

 Whorls (remaining) 7^, short, of slow increase, convex ; the last has a short roundly con- 

 tracted base. Suture in itself indistinguishable, but well marked by the contraction of 

 the whorls and the sutural furrow; it is little oblique. Mouth gibbously oval, pointed 

 but hardly sinuated above, but with a rather strong, roundly hollowed, and somewhat 

 oblicpie gutter truncating the pillar. Outer lip thick and strong, but bevelled from with- 

 out to a fine level edge ; its direction is nearly straight for half its course, when it curves 

 round obliquely to the gutter edge, where it is hollowed out roundly. Inner lip rather 

 thinly continuous across the body, slightly concave in passing over into the short stumpy 

 pillar, whose profile lines are triangular. H. - 13 in. B. 0'055. Mouth, outside of lip, 

 height 0*05, breadth 0-047 ; inside, height 0'033, breadth 0-031. 



This species belongs to the group of the sharply reticulated Rissoinas, and has something of the 

 style of Rissoina sagrayana, d'Orb., or Bissoina media, Schwartz. Than Bissoina nitida, A. Adams, 

 it is much smaller, and is much more sharply and more sparsely ribbed. Bissoina fusca, Gould, from 

 Hong Kong, lacks the furrow and fold round the point of the pillar. 



5. Fenella, A. Adams, 1864. 



Mr Adams considers this genus most nearly connected with Bissoa (subgenus Alvania) ; but his 

 description of the animal hardly justifies this estimate ; and, so far as I am aware, its true place is 

 undetermined. 



Fenella elongata, Watson (PI. XXXIV. fig. 4). 



Fenella elongata, "Watson, Prelim. Report, pt. 7, Journ. Linn. Soc. Lond., voL xv. p. 249. 



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

 Island, West Indies. 390 fathoms. Pteropod ooze. 



Station 78. July 10, 1873. Lat. 37° 26' N., long. 25° 13' W. Off San Miguel, 

 Azores. 1000 fathoms. Volcanic mud. 



Shell. — Small, high, narrow, conical, translucent white, with deep wide suture and 

 rounded whorls and base. Sculpture: Longitudinals — on the last whorl there are 12 to 

 13 narrow and sharply-rounded, but not high, ribs, parted by furrows about four times 

 their width ; they cross the whorls with a slight obliquity, and are abruptly interrupted 

 on the last whorl by the edge of a basal tabulation, where the entire base is levelled up 

 to the summit of the ribs, which thus all but disappear. On the earlier whorls the 

 ribs are rather fewer in number, and are somewhat closer set ; on the third they are 



