T urri-s.] GASTROPODA. 469 



KEY TO GENERA. 



A. Sinus at the angle of the last whorl ; canal moderate or long . . TURRIS. 



B. Sinus at the shoulder of the last whorl ; canal short, sinuate 



at the base. . . . . . . . . . . . DRILLIA. 



G. Sinus contiguous with the suture ; base of canal not sinuate . . SPIKOTROPIS. 

 D. Sinus very faint ; canal very short, not sinuate . . . . BELA. 



Genus 1. TURRIS, Bolten, 1798. 



Turn's, Bolten, Mus. Bolten. (2), 1798, 123. Type : JUurex babylonius, L. 

 Murex (sp.), Linne, 1758. Fus-us (in part), Helbling, 1779. Pleurotoma, 

 Lamarck, 1799. 



Animal having the foot truncated anteriorly, obtuse posteriorly ; 

 tentacles cylindrical, with eyes externally near their base ; teeth of 

 radula falciform, angulated, formula 1+0+1. Radula of Tunis 

 babylonia. L. : Atlas, pi. 1, f. 4. 



Shell turriculated, fusiform ; spire long, sharp ; protoconch conic, 

 the nucleus obtuse ; whorls angled, generally crenulated upon the 

 angle or adorned with spiral cords ; aperture ovate, the columellar 

 margin smooth ; the outer lip with a narrow profound sinus, situate 

 at the angle of the whorl, separated rather distantly from the suture. 



Inhabiting warm seas. 



Subgen. 1. HEMIPLEUROTOMA, Cossmann, 1889. 

 Type: Pleurotoma denticula, Basterot. Coronia, de Greg., 1890 (in part). 



Shell turriculated, nodulous ; spire high, conic ; protoconch the 

 same as in the genus ; whorls usually crenulated, excavated above, 

 with a cord or smooth carina toward the suture ; the last whorl with 

 a sinuous base and a rather short nearly straight canal ; aperture 

 pyriform. suddenly contracted towards the. canal ; outer lip strongly 

 convex, with a somewhat rectangular sinus at the row of nodules ; 

 inner lip thin and very little callous. 



KEY TO SPECIES. 



A. Shell with prominent spiral ribs, 5 on the penultimate whorl, 



crossed by growth-lines . . . . . . . . alticincta. 



B. Shell with but little sculpture ; the whorls with 2 keels, one above 



the middle and one above the suture ; strong growth-lines . . ischna. 



1. Turris alticincta, Murdoch and Suter, 1906. Plate 21, fig. 1. 



Pleurotoma (Hemipleurotoma) alticincta, M. & S., T.N.Z.I., xxxviii, 1905 

 (1906), 285, pi. 22, f. 12, 13. 



Shell rather small, turriculate, subcylindrical, with a long spire, 

 deeply sulcate whorls, an oblong aperture which is slightly shorter 

 than the spire, and a short canal. Sculpture : On the upper spire- 

 whorls a few minute spiral striae, the next with 4 distinct cinguli, on 

 the succeeding a minute fifth spiral arises at the suture, which on the 

 penultimate strengthens and about equals the adjoining revolving 

 ribs ; the cinguli are strong, rounded, and adorned with minute spiral 

 threadlets, absent in the grooves ; the latter are deep, somewhat 



