BEAUTY OP SHELLS. 337 



highly ornamental, but the properties which render them 

 so do not apparently conduce to any other purpose. In 

 shells and flowers, the principle of beauty holds a con- 

 siderable place in their composition, and is more prominent 

 than in animals. Wliy, for instance, are the shells of the 

 genus Cardium, or Cockle, frequently of a dark brown 

 colour, varied with white hollow elevated ribs ? Why are 

 those of the Tellina, or Tellen, so remarkable for their 

 beautiful radiations ? Why are so many species of Venus 

 unrivalled in their brilliant tintings and lustre ? — the rich 

 purple Ve7ius mercenaria, or Money Yenus, especially, 

 which is used by the Indians of North America to form the 

 purple and white beads of wampums, or treaty-belts. The 

 processes of animal nutrition, so far as we can see, might 

 have been carried on as well under the sober coating of 

 the garden-snail. This variety is not the effect of age, nor 

 of any declension in the vigour of the subject, for the 

 young and active are generally most distinguished for the 

 brilliancy of their tints ; it is evidently independent of the 

 inhabitant. In none of the numerous family of Testacea 

 is it more remarkable than in the hundred and fifteen species 

 of this elegant genus, most of whicli are celebrated for the 

 smoothness and briUiancy, as well as the rich and high 



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