178 COLUMBELLID^. 



within its shell, it is said, when irritated, to spontaneously detach 

 a portion of this foot. 



SILIA, Mayer, 1876. Ribs deflected, spire short, suture not deep. 

 H. Zitteli^ Mayer. Eocene. 



HARPOPsis, Mayer, 1876. (Buccinopsis, Bayle.) Shell smooth, 

 the last whorl slightly angulated below the suture, very large and 

 long ; mouth small, lengthened ; inner lip with thin callus; outer 

 lip with slight posterior sinus. H. stromboides, Lara. Eocene ; 

 Paris basin. 



Family COLUMBELLID^, 



Shell oval, covered by an epidermis ; spire more or less 

 developed, generally short; aperture narrow, elongated, termi- 

 nating in a very short anterior canal ; columellar lip usually den- 

 tate ; outer lip mostly thick, incurved in the middle and internally 

 crenulated. Animal with a large, flattened head ; the foot narrow, 

 oval, elongated ; the siphon scarcely longer than the canal of the 

 shell. Operculum very small, lamellar, corneous. Dentition 

 (X, 20). 



CoLUMBELLA, Lam., 1799. 



Etym. — Diminutive of columba, a dove. 



Syn. — Columbus, Montf., 1810. Peristera, Rafinesque, 1815. 

 Pygmsea (Humphrey), Morch, 1858. 



Distr. — 300 sp. Mostly subtropical; Atlantic Coast, TJ. S., 

 West Indies, Mediterranean, India, China, Japan, Philippines, 

 Australia, Pol3mesia. W. Coast of America. Fossil. Tertiary. 

 C. viercatoria, Lam. (Ivi, 78). 



Shell strombiform or obovate, smooth or longitudinally or 

 transversely ribbed; internal lip excavated in the middle, crenu- 

 lated or denticulated in front ; outer lip inflected and internally 

 thickened and crenulated in the middle. 



NiTiDELLA, Swaiuson, 1840. Shell oval, smooth, spire elevated ; 

 aperture somewhat effuse below ; columella with two small ante- 

 rior plications, outer lip somewhat thickened. C. nitida, Lam. 

 (Ivi, 79> 



ALIA, H. and A. Adams, 1853. Shell thin, smooth, spire mod- 

 erate ; aperture oval ; inner lip finely crenulated, outer lip thick, 

 not callous in the middle, striate within. C. unifasciata, Sowb. 

 (Ivi, 80). 



MITRELLA, Risso, 1826. Shell mitriform, smooth, spire elevated ; 

 columella smooth or with a few anterior rugosities ; outer lip 

 smooth, or crenulated within. G. lactea, Duclos (Ivi, 81). 



ATILIA, H. and A. Adams, 1853. Shell fusiform, longitudinally 

 plicate ; spire elevated, sharp ; last whorl suddenly narrowed in 

 front. Csuffusa, Sowb. (Ivi, 82). 



ANACHis, H. and A. Adams, 1853. Shell oval-fusiform, longi- 

 tudinally ribbed ; spire elevated ; aperture narrow ; columella 



