Tun shell, Dolium perdix, showing the wide, spreading foot, 

 long proboscis, small tentacles, and thin shell. (Woodward.) 



same process is resorted to in working out a bas-relief on the entire 

 shell, the latter being placed in a vise to hold it firmly. The home 

 of this industry is at Genoa and Rome, Italy, and for a long time 

 the practice of the art was confined to that country. At the present 

 time it has spread to France, and in Paris alone several thousand 

 people are employed at this work, although the product is not of as 

 fine a quality as is that from Italy. Many beautiful examples of these 

 cameos were ex- 

 hibited in Chicago, 

 in 1893, at the 

 World's Columbian 

 Exposition. 



" A genus related 

 tc the helmet shells, 

 but thinner and 

 more delicate, is the 

 Dolium, or tun shell, 

 which is often beau- 

 tifully colored and 

 delicately sculptured. The animals of the fig shells, a related genus, are 

 very timid, but when undisturbed are also very lively, crawling over the 

 ground with great rapidity. When in motion, the long, tapering tentacles 

 are fully extended, and the siphon is directed almost straight ahead, 

 instead of over the back, as in many other snails. The colors of the 

 animals vie with those of the shells, their bodies being marbled with 

 violet and pink, and with spots of white here and there. The large, 

 black eyes are very conspicuous. The foot and mantle are so large 

 that the shell is frequently almost buried from sight. There are ten 

 species of fig shells, and they may be found in the warm waters of the 

 West Indies, the Philippine Islands, and the west coast of central 

 America. One fine species, Pyrula papyratia, lives in Florida, where 

 it may be collected in large numbers. 



<' Probably no more distinct family of mollusks exists than the 

 Conidce, or the family of cones, their beautifully decorated shells and 

 the large number of species making them a favorite group with col- 

 lectors. The shell is in the form of an inverted cone and gracefully 

 rounded, the aperture being but a narrow slit extending nearly the 

 whole length of the shell. The colors of the cones are always very 

 brilliant, although w r hen they are alive the shell is not so highly pol- 

 ished as that of the Cyprceas, owing to the presence of a horny epi- 

 dermis. About three hundred species of cones are known; these live 



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