The Olive Shells. Rice Shells. Harp Shells 



yellow and white and highly polished. The basal grooves lead to 

 a deep umbilicus. Length, 2 to 3 inches. 

 Habitat. — West Indies. 



THE HARP SHELLS 

 Genus HARPA, Lam. 



Shell large, ventricose, longitudinally ribbed; columella 

 polished, broad and fluted above, narrow and smooth below; 

 outer lip thickened; aperture large; operculum, none. 



A very distinct genus of nine species, distributed in all 

 tropical waters except those of the Atlantic Ocean. 



The general outline of these shells, and the parallel series 

 of ribs stretched from spire to base, justify the name. Harpalis, 

 Harparia, Lyra, Cythara, Buccinum — all these generic names 

 have been applied to members of this small group. All credit 

 them with grace of form and perfection of fmish befitting instru- 

 ments of music. To these attributes are added richness of colour- 

 ing that alone would rank them above most other shell families. 

 Combining colour harmonies of unsurpassed beauty with sym- 

 metry and grace of line and curve, the harp shells have perhaps 

 excited more universal' admiration than any other group of the 

 "aristocratic shells." 



There is no door in a harp shell shutting the world out when 

 the moUusk would retire and rest. There is not room enough 

 inside for the animal. The head and tentacles, and the crescent- 

 shaped foot protrude when the body is completely withdrawn. 

 The colours of these fleshy parts rival those of the shell. In 

 Mauritius the natives go out at low tide with net rakes to catch 

 harps on the sands. The mollusk crawls rapidly along to escape 

 the net. When hard pressed it withdraws as far as possible 

 within its shell, and may cut off part of the foot by pressure 

 upon the lips! This observation was made upon H. ventricosa. 



The shell grows through a certain period, then ceases for a 

 time. In preparation for this period of rest the lip is thickened. 

 The strong ribs of the harp thus correspond to the varices of 

 Murex and Triton. The shorter the food supply, the closer the 

 ribs of the shell. The mode of feeding of these large mollusks 



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