20 GLABELLA. 



The light-colored varieties (fig. 82) have been called M. are- 

 naria by Morch. 



M. OBTUSA, Sowb. PI. 6, figs. 83, 84. 



Shell wide, with short conical spire ; nearly the entire surface 

 covered with longitudinal obtuse ribs ; white with revolving 

 series of light chestnut spots and broader bands of the same 

 color upon the shoulder and near the anterior extremit}^ ; lip 

 thickly spotted. Length, -75-1 'S inches. 



Habitat unknown, probably W. Africa. 



The long ribs, rather a peculiar feature in the genus, are not 

 shown in Sowerby's figure, although indicated in his description. 

 M. viirabilis, Barclay (fig. 84), is a finely grown specimen. 



M. Adansoni, Kiener. PI. 6, figs. 85, 86. 



Light yellowish or orange-brown, with zig-zag longitudinal 

 shadings, and irregular longitudinal narrow dark brown lines. 



Length, •9-1-25 inches. 



Senegal and Oambia, West Africa. 



M. Bella, Sowb. (fig. 86), described from a single specimen, 

 and remaining unique, is probably a dwarfed individual of this 

 species. 



M. Davisiana, Marrat. 



Shell like 31. Bellii, Sowb., but much smaller, thicker, narrower, 



and lighter-colored, longitudinal lines distant; lip crenulated 



within, thickened without, columella four-plicate. 



West Africa. 

 Unfigured. 



M. NODATA, Hinds. PI. 6, fig. 87. 



Yellowish brown or grayish, with undulated, thin, dai'k choco- 

 late longitudinal stripes, studded at intervals by spots forming 

 revolving series. No ribs. Length, 1 inch. 



Cape Blanco, W. Africa ; in sand at 12-15 fathoms. 



Closely allied to the following species and only distinguished 

 from it by the spots. 



M. Cleryi, Petit. PL 6, fig. 88. 



Shell smooth ; light yellowish or white, with faint gra}^ bands, 

 and longitudinal, undulated chocolate stripes. Length, -9 inch. 



West Africa. 



