1 



GARRETT: ON POLYNESIAN MITRID^. 1 5 



the reefs on sandy bottom in the upper region of the lamina- 

 rian zone. 



They differ remarkably in the size of adults, averaging 

 from 2^^ to 6 inches in length. We have now before us a fine 

 Society example which is a little larger than Reeve's beautiful 

 figure. 



22. Mitra eburnostoma sp. nov. 



Shell cylindrically fusiform, solid, creamy-white, sparingly 

 mottled with brown ; spire rather long with slightly convex 

 outlines ; suture crenulate ; whorls 9, flatly convex, spirally 

 ridged, ridges rather small, unequal, angular, decussated by 

 longitudinal incised lines which gives the surface a depressly 

 granulated appearance ; aperture ivory-white, half the length 

 of the shell ; columella with four plaits. 



Length 41, diam. 13 mill. (Coll. Garrett). 



Hab. Parfmotu Islands. 



A very rare species of which we found two examples 

 buried in sand in the upper region of the laminarian zone. 



The sculpture is almost precisely the same as in M. 

 sphcerulaia, but may be at once distinguished from that 

 species by its paler color, more slender form and pure white 

 aperture. The latter character connects it with AI. scabrius- 

 cula, but the sculpture is quite different in the two species, 

 and the shape is more regularly fusiform. The outlines are 

 exactly similar to M. fasciata. 



23. Mitra eburnea sp. nov. 



Shell small, fusiform, smooth, shining, base strongly 

 recurved, ivory-white \ spire rather long, acute, with flattened 

 outlines ; whorls embryonal 2, smooth, normal whorls 8, 

 planiform, last one convex, strongly contracted at the base ; 

 striated with rather crowded spiral impressed lines and the 

 upper whorls with fine spiral granulated ridges ; aperture 



