176 OLIVID^. 



very short, the suture not canaliculated to the apex ; aperture 

 rather large and wide, inner lip somewhat tortuous, with a large 

 callosity behind, incurved in the middle, and two or three oblique 

 anterior plaits. Head and tentacles concealed ; mantle with a 

 large, thick, fleshy appendage behind, partially covering the 

 spire ; foot very voluminous, truncate posteriorly, shield with 

 the side-lobes very large and rounded. Operculum small, half 

 ovate, with subapical nucleus. Appears to connect Oliva with 

 Ancillaria. Brazil, W. and S. Africa. 0. Brasiliana, Lam. 

 (Ivi, 11). 



PLOCHEL^A, Gabb. Shell olive-shaped, suture nearly obsolete, 

 as in Ancillaria ; spire short ; outer lip internally thickened in 

 the middle ; iniier lip callous, with several transverse folds, of 

 which the upper are smallest ; columella strongly recurved at 

 the base,like a Dibaphus. P. crassilabr a, Gsibh. Tertiary ; West 

 Indies. 



Subfamily ANCILLARIINJS. 



Head concealed ; eyes none ; tentacles rudimentary ; mantle 

 with a tapering lobe in front ; foot voluminous, bifid behind, 

 shield-grooved on the upper surface, side-lobes not much pro- 

 duced. Operculum small, ovate, acute, sometimes entirely 

 wanting. Shell usually polished ; sutures covered by callus ; 

 whorls smooth ; aperture effuse, the columella variously grooved 

 and twisted in front. 



MoNOPTYGMA, Lea. 



Syn. — Not Monopt3^gma, Gray, Chiloptygma, H. and A. Ad. 



Distr. — Fossil. Eocene ; United States. M. Alabamensif^ ^ Lea 

 (Ivi, 14). One recent species, M. exigua, Sowb., is possibly a 

 monstrosity. 



Shell with elevated spire and callous columella, the latter with 

 a subcentral conical tooth-like callous projection. Dr. Lea's 

 second species of his genus is an Actaeon. 



Ancillaria, Lam. 



Etym. — Ancilla, a maiden. 



Syn. — Ancillopsis, Conr. Sparella, Gra,j. Anaulax, Roissy. 

 Ancitla, Lam, Amalda, H, and A. Adams. Sandella Gray. 



Diatr. — IT sp. Red Sea, Indian Ocean, Australia, Japan, West 

 Indies. Fossil. Eocene — ; U. S., Eur. A. Tankervillei^ '&w?im%. 

 (Ivi, 73), 



Shell oblong or subcylindrical, thick and smooth in the typical 

 species ; body-whorl usually swollen ; sutures covered by enamel ; 

 aperture broadly effuse below ; columella (typically) not umbili- 

 cated, with a few oblique anterior plaits. The revolving basal 

 groove ends occasionally in a slight anterior labral projection or 

 tooth. 



