138 CANCILLA. 



M. FORMOSA, A. Ad. PL 39, fig. 163. 



Whitish, clouded with chestnut ; slightly round-shouldered. 



Length, 1-4 inches. 



Moluccas. 



I have not seen either this or the preceding species : the 

 figures look much alike, and the difference in coloring is of little 

 account, but M. formosa appears to have finer sculpture. 



Section Cancilla, Swainson. 



Shell fusiform, slender ; with revolving, linear, elevated ridges, 

 and no longitudinal ribs; outer lip thin, not dentate within. 



M. FILARIS, Linn. PI. 40, figs. 174-176, 180. 



Pinkish white of yellowish white, with elevated, narrow, brown, 

 beaded ridges. Length, 1-25-1*75 inches. 



Mauritius, Philippines, Polynesia. 



Mr. Garrett considers M. nexilis, Martyn, a distinct species ; 

 it is a shorter, stouter form than the type, but intermediate con- 

 ditions are not wanting. Philippi considers M. filosa, Born 

 (= filaris, L.), the equivalent of the obese form, and makes of 

 the narrow form a var. gracilis, whilst a small race is designated 

 as var. Bernardiana. 



Yar. NEXILTS, Martyn. Fig. 174. 

 Var. BERNARDIANA, Phil. Fig. 180. 

 Yar. CIRCULATA, Kiener. Fig. 176. 



The ridges are uncolored, sharper, devoid of granules ; in 

 some specimens the intermediate revolving striae are most prom- 

 inent, others are cancellated between the ridges, and others again 

 show mostly the longitudinal inter-costal striae. M. circulata 

 has usually been considered a distinct species, but even in the 

 coloring of the ribs there is a gradual change from the uncolored 

 typical M. circulata to the full-colored M. filaris. 



M. CREBRILINEATA, Sowb. PI. 40, fig. 170. 



This little shell resembles filosa ( filaris), but is narrower, 

 and has more numerous and finely beaded ridges. Length, '8 inch. 



Mauritius. 



Probably not distinct from filaris, but I have not. seen a 

 specimen* 



