50 VOLVARTA. 



M. Mexicana, Jousseaume. PI. 13, fig. 1. 



Rather solid, opaque white, with four ver}' obscure bands, 



columella four-plaited. Length, T mill. 



Mexico . 

 Possibl^^ a variety of 31. lactea, Kiener. I am not acquainted 

 with the species. 



M. AVEXA, Yalenc. PI. 13, figs. 2-5, 8. 



White or yellowish white, with three broad bands of brownish 



3^eIlow ; columella four-plaited. Length, •45-'6 inch. 



West Indies. 

 Var. Beyerleana, Bernard! (figs. 3, 8). 



White or rosy-white, with the bands of rose-color ; it is clearl}'^ 

 connected by intermediate shades with the t3'pe. Some of these 

 intermediate states are M. livida, Reeve (fig. 4), M. ejfulgens, 

 Reeve, and 31. guttula. Reeve (fig. 5* . 



Yar. AA'ENELLA, Dall. 



Shell exceedingly variable in proportions ; spire short, obtuse, 

 sometimes almost suppressed ; color light 3'ellow or yellowish 

 white, with a faint white line bordering the suture ; general 

 outline elongated ovate ; aperture long, narrow behind (where 

 the outer lip is thickened and a little inflected \ wider in front 

 (where it is thin), and a little flaring at its (widest) anterior 

 termination; columella with four subequal folds, all rather 

 oblique; outer lip simple, thickened behind, where the line of 

 callus may extend to the suture or fall considerably short of it ; 

 slightly concave in the middle, where its edge is even turned in 

 a little ; scarcely, if at all, produced forward ; whorls not at all 

 or very slightly shouldered, three or four in number. In the 

 form with the short rounded spire, the outer lip is straight, not 

 inflected, and more evenly thickened along its whole length ; the 

 anterior end of the aperture has the outer lip obliquel}' cut off, 

 and not flaring. The whole form is more evenly ovate-cylindrical. 

 The measurements of the long- and short-spired specimens are 

 respectively as follows: — Lon. of shell, 12"0 and 9"5 ; of Avhorl. 

 10-25 and 9*0 ; of aperture, 9-5 and 8-25. Max. lat. of shell, 5-0 

 and 3-'I5 ; lat. of aperture at middle part, 1-0 and 10 mm. 

 Off Cape iSan Antonio, 1002 fms.; Station Ti, 229 and 



152 fms.; Station 2, 8flo fiithoms, Cnribbeaiu 



