SCABRICOLA. 135 



M. SUCCINCTA, Swainson. Habitat unknown. 



M. SUBTEXTURATA, Garrett. Society Islands. 



Unfigured species, said to be allied to M. texturata. 



M. CRENIFERA, Lam. PI. 39, figs. 152, 164, 165. 



Yellowish or pinkish white, with two irregular clouded bands 

 of chestnut or chocolate color, or sometimes irregularly macu- 

 late ; the whole surface is closely decussated. Length, 2 inches. 

 Mauritius, Manilla, Bed Sea, Indian Ocean. 



This species is so well-known under its present name that it 

 would be injudicious to revive for it the previously given name 

 of M. clathrus, Gmelin. M.pretiosa, Reeve (fig. 164), is a young 

 shell of this species; M. Antoniae, H. Adams (fig. 165), is 

 synonymous with it. 



M. SCABRIUSCULA, Linn. PI. 39, fig. 158. 



Whitish, clouded with chestnut or chocolate-brown, often 

 appearing like interrupted spiral series on the revolving ridges. 



Length, 2-2'5 inches. 



Philippines ; Viti Islands, sandy stations. 



A stouter species than M. crenifera, the prominent spiral 

 ridges alternating with impressed strise, the longitudinal sculp- 

 ture subordinate. The animal is diluted white, maculated with 

 numerous small opaque white spots. 



M. HELVACEA, Phil. 



An unfigured species, from China, said to be intermediate 

 between M. scabriuscula and M. Isdbellina. Sowerby does not 

 allude to it, although published twenty years before the appear- 

 ance of his monograph, and I suppose it may be considered a lost 

 species. So much allowance must be made for the personal equa- 

 tion in descriptive and distinctive characters that in these days of 

 minute distinctions it is rarely worth while to attempt to identify 

 unfigured shells, or to reproduce the descriptions for the con- 

 founding of students. In nine cases out of ten a description can- 

 not be made sufficiently accurate to identify a species positively, 

 and in ninety-nine cases out of a hundred it is sufficiently indefi- 

 nite to secure a wrong identification from those who attempt to 

 fit it to their unnamed species. Conchologists have .suffered more 

 than enough in endeavoring to acquiesce in the cheaply bought 

 glorification of naturalists ; it is full time to inaugurate a reform 



