PHYLLONOTTJS. 101 



M. BICOLOR, Yal. PI. 23, fig. 204 ; pi. 22, fig. 203. 



Resembles the preceding species but is distinguished by its 

 less luxuriently fimbriated and spined varices, which are fewer in 

 number, usually four or five, with single spinous ribs in the 

 interstices. Exterior light yellowish brown, aperture pink, which 

 does not become black on the columellar lip. Length, 6 inches. 



Panama to Guaymas. 



M. hippocastaneum, Phil., (fig. 203), is a young specimen of 

 this shell, in not very good condition, said by him to come from 

 Chili. 



M. IMPERIALIS, Swains. PI. 23, fig. 206. 



Four or five varicose, the varices stout; rounded, depressed 

 tuberculate, but scarcely spinous ; usually an interstitial, nodu- 

 lous rib ; spire pointed, conical. Shell very thick and heavy. 

 Light brown, sometimes with a darker band ; aperture sulphur- 

 yellow or pink, in the latter case sometimes black on the colu- 

 mellar lip. Length, 4 inches. 



Isle of Margarita, W. I. 



This shell is generally attributed to the Pacific coast of North 

 America, which appears to be a mistake. Its different zoological 

 region taken in connection with its great solidity may serve to 

 distinguish it from M. bicolor and M. regius, both of which it 

 mimics so closely in coloration ; it appears to hold the same re- 

 lation to these species that the var. M. calcitrapa does to M. 

 brevifrons. It also has relationships with the West Indian M. 

 pomum. 



X- 

 fc -X- 



M. SAXATILIS, Lam. PI. 27, fig. 245 ; pi. 26, fig. 226. 



Varices six to eight, singly spinous, the spines somewhat fron- 

 dose, those on the shoulder of the whorls usually larger and 

 curved ; T*o,_interstitial ribs. Light yellowish brown, usually 

 more or less pink-banded ; aperture pink, with three or four 

 darker bands. Length, 6 to 8 inches. 



Ind. 0., West Coast of Africa. 



The Museum of the Academy of Natural Sciences of Phila- 

 delphia possesses a fine series of this species from the Gabon 

 coast of Africa, some of which have all the richness of color and 



