OVULA. 93 



ii 



The last family of the order Trachelipoda 

 is Convoluta, which contains many very fine 

 genera. 



" They are the following : 



Ovu/a Bulla. 



CyprcBa The same. 



Terebellu m ...Bulla. 

 Ancillaria. 



Oliva Voluta. 



Conus The same. 



" The general characters of this family are the 

 following : 



" Shell without a canal, the base of the aper- 

 ture sloping, or effuse, the spire compressed, the 

 last volution almost covering the rest. 



^' Oviila, you will recollect, was formerly con- 

 founded with the Bulla genus : the form is egg- 

 shaped, the outer lip toothed in one division, 

 smooth in the other ; the shells are white and 

 polished, particularly O. oviformis, the poached- 

 e^g^ from the Moluccas. 



" O. volva, the weaver's-shuttle, is a rare and 

 highly- valued species. It is nearly globular in 

 the middle, and is terminated at each extremity 

 by a long beak : it comes from the West Indies. 

 O. gihhosa is a common species ; the shape is ob- 

 long, with a ridge in the centre. 



