UNIVALVE MOLLUSC A. 



445 



white, ornamented with numerous broad, black, round spots, much 

 scattered, and a straight dorsal line, brown above, and very white 



Fig. 270. — Natural size of Ovulum oviformis (Lamarck). 



below. It has generally twenty-three teeth on each edge, quite white. 

 Somewhat resembling the Tiger Cowrie is the Cyprcea paiiiherina 

 (Fig. 269), which is perhaps a variety of the .same species. Another 

 remarkable species is Cyprce argiis, as represented in 

 Figs. 253 and 254. 



The genus Ovulum, so called from their egg-shaped 

 form, occupy a place next to the Cowries in some 

 systems. The shell is highly polished, white or rose- 

 coloured, oblong or oval, convex, attenuate, and acu- 

 minate at the extremities without apparent spire, the 

 edges milled within the long, narrow, and curved open- 

 ing, with teeth upon the left- edge, and with a few 

 ripples on the right edge. The species of Ovulum are 

 inhabitants of the Indian Ocean and Chinese Seas. 

 Some few species, however, belong to the Mediterranean and the 

 Black Sea. The three species represented in Figs. 270, 271, and 

 272, present very singoilar contrasts of form and size. 



The second family, Volutidce, contains the genera Cytnba, Mar- 

 ginella, Mitra, and Valuta. 



The Mitres are so called from their resemblance to the bishop's 



Fig. 271. 



Ovulum cornea 



(Lamarclc). 



