174 PL AN AXIS. 



ceding, with lighter sulci, disappearing in the middle of the 

 whorls. 



18. siMiLis, f. 36, Smith. — P. acuto similis, fuscus ; anfrac- 

 tibus omnino distanter sulcatis. — The grooves do not disappear 

 in the middle of the whorls. 



19. Hanleyi, f. 37, Smith. — Acute pyramidatus, fuscus, 

 loevis ; anfractibus moderate convexis, supra infraque sulcatis ; 

 ad suturam unifasciatus ; apertura intus tenuiter lirata, rima 

 suturali subrotunda. — The little channel formed at the 

 junction of the life outer with the columella lif) is rather 

 more rounded than in most species. 



20. NIGER, f. 38, Quoy. — Niger, Isevigatus, tenuiter sul- 

 catus ; apertura subpatula, canali postico subrotundo. — P. 

 Hanleyi differs from this in several slight particulars, as may 

 be seen by comparing figs. 37, 38. 



21. ATER, f. 40, Pease. — Brevis laevis niger ; spira brevi ; 

 apertura subtrigona, intus lirata, canali postico nullo. — A 

 small, rather short black shell, rather expanded in the last 

 whorl. 



22. ABBREVIATUS, f. 41, Pease. — Brevis Isevis niger, obliqua ; 

 apertura subtrigona expansa, intus lirata, canali postico lato. 

 — More oblique than the preceding, with the outer lip more 

 expanded, and a rather wide posterior canal in the mouth. 



23. piLiGER(Holcostoma), f. 19, Phillppi. — Ovatus fulvus, 

 leviter fusco fasciatus, Isevis ; spira brevissima ; ultimo an- 

 fractu magno, medio ventricoso ; apertura albida, subovata 

 columella brevi obliqua lata truncata. — Differing from all 

 other species in its oval shape and the size of the last whorl. 



24. TENUIS, f. 5, Smith. — Elevatim pyramidatus tenuis 

 politus, pallide ta?niatus ; anfractibus convexiusculis tenuis- 

 sime, sulcatis. — Pale, elevated, and thin, with extremely 

 slight spiral lines. 



25. INEPTDS, f. 6. Gould. — Elevatim pyramidatus, lineis 

 distantibus pallide zonatus, spiraliter sulcatus. — More elevated 

 than most of the small lineated species. 



26. zoNATDS, f. 7, A. Adams. — P. inepto similis sed magis 

 pyramidatus ; ultimo anfractu medio et infra medium rubro- 

 lineata ; apertura subtrigona, labio externo incrast-ato, denti- 

 eulato. — A single red line appears above the suture of the 



