The Olive Shells. Rice Shells. Harp Shells 



The San Pedro Rice Shell (O. Pedroana, Conr.) has a slim, 

 shining little shell, coloured bluish or brown, and sometimes 

 striped with yellow. It is about ^ inch long. It lifts up a small 

 pellet of sand, as if by thrusting up its head to see if the tide has 

 gone away and left it. I have found them in plenty on San 

 Pedro Bay, Cal. 



The Twisted Olivella (0. intoria, Cpr.) is small, too, but 

 stout in build compared with the last species. The pale surface 

 is spirally striped with yellow. The suture is deep; the columella 

 bears one fold, and spreads into a large callus above. The outer 

 lip is thin and curved at the base. 



Habitat. — California. 



Genus ANCILLARIA, Lam. 



Shell oliviform, of few coils, thin, polished; sutures filled 

 with callus; lip flaring, frequently squared anteriorly; a strong 

 spiral ridge ends in a tooth near base of body whorl; foot 

 fissured, very large, reflected over shell; mantle prolonged 

 in front into a long siphon; tentacles united to form veil; eyes 

 wanting. 



A small genus of seventeen species of active, gliding mol- 

 lusks, in tropical waters, chiefly East Indian. 



The Cinnamon Ancillaria {A. cinnemomea, Lam.) is the 

 type, though by no means as large as the largest species 

 in the genus. The colour is cinnamon yellow, with two 

 bands, brown and white, around the spire. The lining is a 

 paler tint. The flaring lip has a squarish corner below. 

 The white columella bears fine oblique striations. The 

 revolving basal sulcus ends in a tooth on the lip. Length, i 

 to \\ inches. 



Habitat. — Red Sea, Persian Gulf. 



A mauritiana is like a melon shell in form and in 

 the capacity of its deep aperture. Its colour, thinness and 

 smooth surface are also suggestive traits. Some are pure 

 white; all have a sliiny white columella. Length, if to 2^ 

 inches. 



Habitat. — Madagascar, Australia. 



The Polished Ancillaria {A. glabrata, Linn.) has a spire as 

 long as the wide aperture. This handsome fusiform species is 



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