MOLLTJSOA OF THE ' CHALLENGER ' EXPEDITION. 331 



edge retreats and is subemarginate on the base, where it is 

 considerably thickened by the extension of the pillar-tooth, whicli 

 is continued round the front within the edge of the lip, and 

 separated from the edge by a minute furrow. Top : the shell is 

 slightly contracted, and then sharply and flatly truncate ; round 

 the edge and coiling in to the centre is a sharp, expressed keel, the 

 whole interval between one keel and the next is occupied by the 

 deep, perpendicular-faced sutural canal, the horizontal top of the 

 whorl, and the extracarinal furrow ; the apex is perfectly flat, and 

 is minute and regularly in-coiled. Inner Up : a strongish glassy 

 defined callus runs down the rather cylindrical body, disappears 

 in the extracolumellar furrow, and reappears in the extreme 

 edge of the outer lip ; a strong oblique tooth twists round the 

 base of the pillar, is flattened hack on the pillar, and is continued 

 in a small intralabral callus on the base ; behind the pillar-edge is a 

 strongish but shallow furrow, but no umbilical chink. H. 0'083. 

 B. 0"042. B. of mouth at same place, 0'009, 



This species is at first sight, and especially in rolled specimens 

 where the sculpture is effaced, deceptively like U. arattcs ; it is 

 really, however, quite different, and in particular the difference 

 may at once be recognized in the top of each. The species seems 

 considerably to resemble B. (Tornatind) polita, A. Ad., from 

 Manilla, but the lip is not posteriorly produced. 



6. Uteictjltjs (Toenatina) pachts, n. sp. (jtayys, broad.) 

 St. 169. July 10, 1874. Lat. 37° 34' S., long. 179° 22' E. 

 N.E. from New Zealand. 700 fms. Grey ooze. Bottom 

 temperature 40°. 



Shell. — Eather large, gibbously oval, being tumid in front 

 and contracted upwards, truncated above where the edge is 

 carinated and furrowed, with an impressed top and a papillary 

 apex. Sculpture. Longitudinals — the lines of growth are few, 

 sinuous, and very slight. Spirals — round the edge of the im- 

 pressed top is a rounded keel, with an exterior strongish rounded 

 furrow, outside of which is a narrow sharpish keel ; within the 

 apical pore the whorls are sharply keeled above the channelled 

 suture ; the only other trace of spiral striation is behind the outer 

 lip, where the fresh shell shows some trace of a spiral texture. 

 Colour horny yellowish white. Mouth club-shaped, large, the 

 full length of the shell, being a little produced posteriorly, shortly 



