GASTEOPODA. 93 



The shells of this Class of animals are among 

 the most beautiful of natural objects ; and when 

 we consider that they are prepared for the cabinet 

 without difficulty, preserved without expense, and 

 free from any liability to decay, we cannot wonder 

 at the ardour with which they have been collected, 

 or the miser-like avidity with which they have 

 been guarded. 



For the gorgeously coloured treasures of the In- 

 dian Seas prices almost fabulous have been given. 

 The sacrifices that wealthy collectors in former 

 days " have made to procure a fine and perfect 

 Many-ribbed Harp, a Gloria maris, or Cedo nulli 

 among the Cones, an Aurora, or Orange Cowry, a 

 Voluta aulica, or Voluta Junonia, &c., are only 

 comparable to the extravagances of those visited 

 by the tulip -mania, when it was at its height." * 

 The shells of our coasts are mostly small and in- 

 conspicuous, compared with those tropical glories ; 

 and yet there are not wanting with us, in the 

 genera Acmea, Trochus, Phasianella, Rissoa, Eu- 

 lima, Chemnitzia, Cyprcea, &c., specimens worthy 

 of high admiration for beauty of colour, delicacy 

 of sculpture, brilliance of surface, or elegance of 

 contour. 



The sexes in some species are united in one 

 individual ; in others they are distinct. In either 

 case the eggs of the marine kinds are deposited 

 in numbers together, enveloped in a common mass 

 of jelly. Those of the Nudibranchs are arranged 

 either in broad frilled ribbons attached by one 

 edge, and coiled spire within spire, as in the 

 Doridida, or in long threads variously twisted, as 



* Penn. Cyclop. ; art. MALACOLOGY. 



