OF CONCHOLOGY. 277 



After examining over a thousand specimens, in good condi- 

 tion, of aS'. morm and its varieties, and comparing tiiem with the 

 figures and descriptions of S. asperum, I am convinced the 

 latter is a variety of the former, contrary to the opinion of 

 Deshayes and Reeve. Mr. Reeve, in his description of S. aspe- 

 rum, omits the character "scabriuscula " given to it by Lamarck. 

 His description of S. morum is correct, and agrees more strictly 

 with the type than that of Lamarck. From it the variation 

 extends beyond S. asperum. The species above described is 

 distinctly ribbed longitudinally and invariably smooth, the whole 

 surface is deeply striate transversely, and the shape is elongate. 

 It may be hereafter connected with S. morum by intermediate 

 varieties, in which case, however, it should retain its name and 

 also *S'. asperum, as varieties. 



SiSTRUM AFFINE. Proc. Zool. Soc, London, 1862. Plate 23, 

 fig. 13. 



Description. — T. crassa, solida, ovata, transversim quinque 

 costata, interstitiis liratis, longitudinaliter irregulariter sulcata ; 

 anfr. superne vix excavatis ; apertura subangusta, oblongo-ovata; 

 nigricans aut intense fusca, columella albida aut chocolato- 

 fusca. 



Dimensions. — Long. 20, diam, 12 mill. 



Locality. — Insl. Kingsmill. 



Shell thick, stout, ovate, transversely ribbed, ribs five, longi- 

 tudinally irregularly grooved, forming oblong nodules, interstices 

 between the ribs filled by two or three small ribs or ridges, 

 transversely striated, whorls slightly concave around the upper 

 part ; aperture rather narrow, oblong ovate ; color black or 

 dark brown, edge of lip black, columella whitish or chocolate 

 brown. 



Since the original description was published, I have received 

 more perfect and mature specimens. I still retain it, although 

 the young especially approach near >S'. atromarginata, Blain., 

 and albomarginata, Desh. It may prove eventually to be a 

 variety of one of those species. Neither, however, are connected 

 with tuberculatum, Blain., as supposed by Mr. Reeve. It will 

 require large collections, from all localities, to define with 

 any degree of accuracy the relative value of the several spe- 

 cies of the above type. 



SiSTRUM SQUAMOSUM, Peasc. Plate 23, fig. 14. 



Description. — T. crassa, abbreviato-ovata, longitudinaliter et 

 transversim nodoso-costata, costis transversis 4 ; lira angusta 



