GARRETT: ON POLYNESIAN MITRID^. 43 



Striae ; whorls 8, flatly convex, last one contracted and 

 slightly granulated at the base ; aperture bluish-white, a trifle 

 less than one-half the length of the shell ; columella with 

 four plaits ; colour dingy-brown, with a single pale revolving 

 line. 



Length i8 mill. (Mus. Godeffroy.) 



Hab. Samoa and Viti Islands. 



Three dead examples found on the fringing reefs at the 

 above groups. 

 ICO. Turricula diachroa (Mitra) Adams and Reeve. Voy. 

 Samar., pi. x., fig. 29. — Mitra Graffi, Crosse, Jour, de Conch,, 

 1867, p. 297, pi. xi., fig, 6. 



Not uncommon under clumps of dead coral in the 

 lower region of the littoral zone, inside the reefs at Samoa, 

 and more rare in the Viti and Tonga Islands. They are 

 usually found associated with Engina mendicaria which they 

 resemble so closely in shape and color as to be easily mis- 

 taken for small specimens of the latter species. 



M. Crosse's- figure, which is slightly enlarged, very cor- 

 rectly represents the usual form. They, however, frequently 

 differ in being more slender, and the ribs are sometimes 

 nearly obsolete. The bands which are generally three on the 

 body whorl, the upper one following the course of the spire, 

 are flesh-white under a thin luteous epidermis on a jet-black 

 ground. The aperture and triplicate columella are tinted 

 with purple-brown. 



Animal black. The foot is oblong, margined with 

 yellow, slightly auriculate in front, and about three-fourths 

 the length of the shell. Siphon rather long, irrorated with 

 white. The pale tentacles are marked by two black zones, 

 loi Turricula discoloria Reeve. Conch. Icon., pi. xxix., 

 fig. 230. 



We obtained several more or less perfect specimens of 



