MANGELIA. 491 



SPURIOUS. 

 M. AcciNCTA, Montagu. 



Murex accinctiis (not of Born), Mont. Test. Brit. Suppl. p. 114. — Laskev, 

 Mem. Werner, See. vol. i. pi. 8, f. 14. — Tuht. Conch. Dic- 

 tion, p. 91. 



Fusus „ Fleming, Brit. Anim. p. 350. — Brit. Marine Conch, p. 205. — 

 Brown, lllust. Conch. G. B. p. 7, pi. 5, f. 14, 15. 



Pleurotoma Fortldensis, Reeve, Conch. Icon. Pleurot. pi. 28, f. 246. 



Small, turreted-subfusiform, not very solid, white or yellowish 

 white, with a rather indistinct narrow spiral fillet of brownish 

 yellow, that runs a little above the middle of the body-whorl, and 

 winds, attenuating as it proceeds, along the base of the smaller 

 volutions. A somewhat obsolete similar one, that revolves be- 

 neath the suture of the principal turns, for the most part (yet 

 not always) accompanies it. Both these coloured zones, when 

 magnified, are perceived to be composed of from two to five paral- 

 lel painted lines. The entire external surface (the apical turns 

 excepted) is roughened with numerous fine raised spiral lines 

 (some of which are at times elevated more than the rest, so as to 

 present an irregular and very slight clathration with the longi- 

 tudinal costse, which traverse the whorls from top to bottom. 

 These last, whose intervals, at least, on the principal whorls, are 

 decidedly broader than the ribs themselves, are sharpish, nar- 

 row, prominent, and not straight, but sinuous, being reflected 

 above parallel to the sinus of the outer lip.' 



In addition to this sculpture, a powerful lens will usually 

 reveal still more minute and densely disposed oblique longitu- 

 dinal lines in the meshes of the decussation. There seem, in the 

 more perfect examples, to be nine volutions, but seven alone are 

 generally visible, as the two extremely small top ones (the apex 

 is very finely pointed) are usually worn away ; they are of mode- 

 rate longitudinal increase, and are very well defined, though the 

 suture is fine and simple, from the contrast between the slight 

 retusion that succeeds the latter, and the convexity of the lower 

 portion of each volution ; the penult turn is rather high. The 

 narrow aperture scarcely occupies two-fifths of the entire length, 

 often, indeed, scarcely more than a third ; it is of an uniform 



