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OVULA. 



Gen. Char. A more or less ovate and gibbose 

 convoluted univalved shell ; the spire con- 

 cealed (or rather none); aperture longitudi- 

 nal, elongated, narrowest at its upper part; 

 the extremities more or less produced, notched; 

 inner lip toothless; outer lip thickened, in- 

 curved. 



A GENUS well distinguished from Bulla, under which 

 Linnaeus had placed its species. It approaches so near 

 to CypraBa, that most conchological authors notice 

 its resemblance ; but unlike that genus its species are 

 rarely of more than one colour externally, and never 

 varieffated. The whole of the outer surface of the 

 shell is when full-grown covered with an enamel-like 

 coat, which is in fact a continuation of the columellar 

 lip : hence that lip (which is itself in other shells only a 

 production of the lining) appears to be wanting : as 

 this coat generally marks the distance the mantle of the 

 animal is able to reach, it is supposed that the animal of 

 an Ovula has a mantle constructed so as to inclose the 

 whole shell, and bipartite, as in Cypraea, which has a si- 

 milar coat. The genus is known by the incurved 

 thickened outer lip of the aperture, opposite to the 

 ventricose smooth body of the shell, instead of to a row 

 of teeth or obtuse laminae as in Cypraea ; some species 

 have a single plait upon the upper part of the co- 

 lumella. The surface is seldom or never furrowed. 



