114 COLUS. 



terranean, East and West Indies, South America, Coast of Cali- 

 fornia, Gallapagos, &c. 



COLUMELLA. A solid column formed by the inner sides of the 

 volutions of a spiral univalve. It is sometimes described as the 

 inner lip of the aperture, of which it forms a part ; but the term 

 would be more properly confined to that portion of the inner lip 

 which is seen below the body whorl, over which the remainder of 

 the lip is frequently spread. All the inner edge of the aperture, 

 including that part of it which covers the body whorl, is called 

 the columellar lip. In fig. 431, the anterior termination of the 

 columella is indicated by the letter c. The axis, is an imaginary 

 line drawn strictly through the centre of the whorls, whether their 

 inner edges form a solid column or not. 



COLUMELLAR LIP. The inner lip. See Columella. 



COLUMELLATA. Lam. A family of the order Trachelipoda, 

 Lam. containing the following genera : — 



1. Mitra. Elongated; aperture narrow ; strong folds on the 



columella ; including Mitrella, Mitreola, Tiwa, and Co- 

 nohelix. Fig. 431, 432. 



2. Marginella. Outer lip reflected ; including Volutella, 

 Persicula, Gibberula, and Glabella. Fig. 437. 



3. Columbella. Outer and inner lips denticulated or granu- 

 lated. Fig. 430. 



4. Voluta. Outer lip thickened ; folds on the columella ; 



aperture generally wide ; apex papillary ; including Sca- 

 phella, Harpula, Volutilithes, Cymbiola. Fig. 433, 436. 



5. Melo. Shell comparatively light ; spire short, sometimes 

 hidden ; apex round, spiral ; folds on the columella la- 

 minar. Fig. 435. 



6. Cymba. Upper edge of the aperture separated from the 

 body whorl by a flat disc ; apex mammillated, irregular ; 

 folds on the columella. Fig. 434. 



7. Volvaria. Cylindrical ; aperture long, narrow ; folds on 

 the columella ; spire hidden. Fig. 439. 



COLUS. Humphrey. Fusus, Lam. 



