CONCHOLOGY. 137 



and striated internally ; colour grayish white, spotted with 

 black, forming oblique longitudinal bands. 



6. Phasianella. The Pheasant Snail. Ten species. 

 ^ This genus of shells is celebrated for the beauty and va- 

 riety of the colouring, disposed in such a nnanner as to re- 

 semble the plumage of a pheasant. 



They are marine shells, many of which are rare and val- 

 uable ; they possess a very distinctive character, that of a 

 slightly projecting angle running along the columella. 



Shell rather thick, oval, smooth, without epidermis, spire 

 pointed ; aperture oval, larger in front, with disunited edges ; 

 the right sharp ; the columella uniting itself a little with the 

 left edge, and offering interiorly a longitudinal callosity; 

 operculum calcareous, oval, oblong, sub-spiral, the summit 

 at one of its extremities. 



Phasianella bulimoides. Phasianella lineata. 



P. rubens. P. nebulosa. 



P. variegata. P. sulcata. 



P. elegans. P. Mauritiana. 



P. Peruviana. P. angulifera. 



P. picta. The painted Phasianella. PI. 24, fig. 2. 



Species smooth, oval, glossy, volutions inflated ; reddish 

 white, with crimson or reddish brown spots ; aperture sub- 

 ovate. 



7. Turritella. The Screw Shell. Thirteen species. 



This genus is easily distinguished from all screwlike 

 shells by a sinus on the right margin of the aperture, not 

 existing in any other shell of similar form. 



Shell marine, turreted, not pearly, rather thin, striated ac- 

 cording to the turning of the spire, which is very pointed, 

 and has numerous whorls ; aperture rounded ; the edges 

 disunited posteriorly ; the right extremity thin, and, when 

 perfect, having a light sinus about the middle ; operculum 

 horny. 



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