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Genus 4. CYPRiEA, Linnceus. 



Animal ; disc ohlong-ovate, in ample folds, more or less acuminated 

 at the extremities, front extremity sometimes truncated ; head 

 obtuse, cylindrical, siphonal appendage broad, short, sometimes 

 fringed at the edge, and disposed in the form of a fan ; tentacles 

 long, stout, eyes situated on a subramose thickening at about one 

 third distance from the base ; mantle produced into two lobes, 

 capable of envelop)ing the shell, furnished with toarts, spinous 

 processes, forked tufted or ramifed f laments, or tubular pajjillcs. 



Shell; ovate or oblong-ovate, ventricose, polished, sometimes nodi- 

 ferous or ribbed, loith the extrernities emarginated ; spire very 

 short, partially or entirely concealed; aperture nearly central, 

 longitudinal, narrow ; lip and columella toothed. 



There is probably no group tliroughout the series which offers matter of 

 so much beauty and interest as the genus Cyprma, whether we regard the 

 animal or the shell. The Cowrey presents the most striking example of a 

 mollusk forming its shell by the outward application of a number of suc- 

 cessive layers of higlily vitrified enameh constituting a superb arch of as 

 many strata, of different colours and design. The changes both of form 

 and colour which the Cypraa shells exhibit at diflferent periods of growth 

 are so dissimilar, that writers of the last century have referred the same 

 species, in different states, to genera widely separated in the system ; and 

 there are instances of three and four species having been founded upon one 

 under different phases of colour. It is, therefore, highly necessary that the 

 collector should assemble specimens of each species of Cowrey characteristic 

 of its different stages of growth, and observe the gradual variations of form 

 and colour that present themselves between the embryo and the adult. 



The fhst stage of advancement produces a simple convolution of shell 

 around the columella axis in the form of a long drawn out Bulla, the colu- 

 mella being smooth, the outer lip thin, and the colour usually diffused in 

 bands of waves. In the second epoch of growth the shell soHdifies, the h]) 

 and columella begin to tliicken, and present gradual indications of teeth, 

 the teeth become more and more perfectly developed, and the dorsal surface 

 is overlaid with a strong coat of livid coloming matter, also diffused in 

 obscure bands or waves. The calcifying energies of the mantle, wliich, ex- 

 tending in two unequal lobes, one from either side of the sheilas aperture, 

 have been cliiefiy exercised during the second epoch of growth upon the 

 back, or dorsal surface, are now more particularly directed to the base and 

 sides. The teeth are strengthened, the sides become thickened with a rich 



