326 REV. E. EOOG WATSOlSr ON THE 



St. 186. Sept. 8, 1874. Wednesday Island, Torres Straits. 

 8 fms. Corai-sand. 



Shell. — Oblong, very symmetrically curved, bluntly pointed 

 above, and still more bluntly in front, wbite, very faintly 

 spiralled, but with the centre part of the body plain. Sculpture. 

 Longitudinals — there are very slight lines of grov^th. Spirals — 

 at the lower end of the shell there are about ten very slight 

 fretted spiral furrows ; those above are rather sparse and 

 irregulai', those toward the point are crowded and feeble ; the 

 larger part of the shell is plain, while above are a few spirals 

 still feebler than those in front. Colour translucent white. 

 Mouth arched; about the middle the arch is flattened and narrowed, 

 broadening a very little above and somewhat more in front ; 

 above it rises bluntly beyond the top of the body, and in front it 

 just passes the point of the pillar. Outer Up is very little 

 curved in the middle, but bends in toward the axis at either 

 end ; its edge retreats a little above, but only very slightly in 

 front. Top is bluntly and roundly pointed. Inner lip : there is 

 a small transparent pointed pad where the outer lip rises from 

 the tip ; the curve of the body is regular, but just at the base of 

 the pillar is a slight contraction ; the pillar, which has a very 

 faint tooth at its base, is slightly oblique, and markedly twisted 

 out to the very point ; it has a flat expanded and broadening 

 front, with a sharp reverted edge, behind which is a rather 

 strongly marked furrow*, but no umbilicus. L. 0"074. B. 

 0"034. B. of mouth at same place, O'OOS. 



In form this somewhat resembles V. angustata, A. Ad., but 

 the sculpture is quite diff"erent. Compared to O. acuminata, 

 A. Ad., the apex of the ' Challenger ' species is not spike-like and 

 the spiral striae are stronger. 



* It is from this feature the name of the species is derived. 



