MOLLUSCA OF THE ' CHALLENGER ' EXPEDITION. 459 



St. 78. July 10, 1873. Lat. 37° 26' N., long. 25° 13' W. 

 San Miguel, Azores. 1000 f ms. Globigerina-ooze. 



St. 85. July 19, 1873. Lat. 28° 42' N., long. 18° 6' W. Palma, 

 Canaries. 1125 fins. Volcanic sand. 



St. 122. September 10, 1873. Lat. 9° 5' S., long. 34° 50' W. 

 Pernambuco. 350 fms. Mud. 



Shell. — High, biconical, a little tumid, carinated, white, thin, 

 faintly, shortly, and obliquely ribbed, with a high, subscalar, 

 small-pointed spire, and a slightly tumid little-contracted base, 

 produced into a long narrow snout. Sculpture. Longitudinals — 

 there are on the last whorl about 20 short oblique folds, which die 

 out almost immediately ; they are highest at their origin below 

 the sinus-area, and are parted by flat intervals somewhat broader 

 than they ; they diminish in number up the spire, and do not 

 reach the lower suture : there are further obsolete lines of growth, 

 which in the sinus-area are strong, and at the suture form sharp 

 little folds parted by wide unequal intervals. Spirals — the sutural 

 area is wide, but scarcely concave ; it is bordered by the blunt 

 angulation forming the keel, which is greatly strengthened by the 

 prominence of the origin of the longitudinal ribs. From the keel 

 downwards the shell is covered by superficial, flattened, irregular, 

 and unequal threads parted by narrower shallow furrows ; these 

 become slightly stronger and more regular on the snout. Colour 

 ivory-white ; the apex is ruddy brown. Spire conical, high, 

 rather narrow, subscalar, sometimes scalar from the squareness 

 with which the sinus-area stands out in the upper 

 whorls. The lines of profile are very much inter- ^S- 2 - 

 rupted by the prominence of the keel. Apex small, 

 ruddy brown, consisting of 4^ conical whorls; of 

 these the lower two thirds is covered with very minute 

 reticulations, while the upper part is scored with 

 minute curved bars, the surface between which is 

 very slightly spirally marked ; it ends in a minute 

 tip a little bent down on one side. Whorls 10 in all, 

 of regular proportions and uniform increase ; they are conical 

 above and cylindrical below the keel ; the last whorl is slightly 

 tumid, and contracts very gradually to a long and small snout. 

 Suture extremely minute as each whorl laps up on the one above 

 it. Mouth oblong, pointed above, and drawn out into a long 

 narrow canal below. Outer lip is pretty regularly arched from the 



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