102 PYRAMIDELLID^. 



amination ; it readily creeps up the deepest glasses, and, 

 however often brushed down, starts again with unabated 

 vigour ^^ (Clark). 



It is the Turbo albidus of Adams's work on the Mi- 

 croscope (from Walker's figure), and Turritella Clealan- 

 diana of Leach. The latter writer was of opinion that 

 " unicus is a very improper name for a species." Surely 

 no shell has a better claim than the present to be con- 

 sidered alone of its kind, or unparalleled, which is the 

 the meaning of the name. It once belonged to the 

 genus Turbo, afterwards to Turritella, then to Chemnitzia 

 (or Odosto7nia), since to Aclis, and it was last trans- 

 ferred to Rissoa. Our dainty Ariel has long served 

 many masters, and perhaps it is time that he should 

 have his liberty. Should such an emancipation take 

 place, and a new genus be required for the distinction of 

 this unique species, Graphis might be a suitable name. 



2. A. As'cARis"^, Turton. 



Turho ascaris, Turt. Conch. Diet. p. 217. A. ascaris, F. & H. iii. p. 219, 

 pi. Ixxxviii. f. 8. 



Shell forming an elongated and slender cone, rather solid 

 for its size, semitransparent, and somewhat glossy : sculpture, 

 strong spiral ridges, of which there are 5 on the body-whorl, 

 and three or four on each of the other whorls ; the uppermost 

 ridge on each whorl is placed at some little distance from the 

 suture ; the base of the shell is smooth ; some slight and flex- 

 uous longitudinal strite or wrinldes may be detected by using 

 a Coddington lens : colour milk-white : spire tapering to ap- 

 parently a fine point: ivliorls 8-9, convex in the middle, but com- 

 pressed or sloping on the upper part of each towards the suture ; 

 they enlarge rather suddenly : suture deep and rather obhque : 

 mouth exactly oval, eifuse below : outer lip slightly flexuous, 

 incurved above, more or less thickened near the edge, so as 

 occasionally to form a varix in an earlier stage of growth : 

 inner lip somewhat thickened and adhering to the pillar, re- 



* A tapeworm. 



