The Olive Shells. Rice Shells. Harp Shells 



is a puzzle. The radula is of the olive type, but very much 

 degraded. The central tooth only is left in each row. 



The Ventricose Harp {H. ventricosa. Lam.) is swollen greatly 

 in the middle; the most characteristic feature is the sharp angular 

 compression of the broad ribs, ending in spinous processes that 

 encircle the spire. Square spots of purplish red form broad spiral 

 bands of dark colour on the paler brownish flesh-coloured ground. 

 The interstices between the ribs are painted with bright festoons 

 of light and dark brown. The bands show plainly in the wide 

 aperture. The columella is widely reflected above and painted 

 with brown blotches. Length, 2^ to 5 inches. 



Habitat. — Mauritius, Indian Ocean, Philippines. 



The Imperial Harp (H. imperialts, Chemn., H. costaia, Linn.) 

 has a far greater number of ribs, and these are rounded and very 

 closely set. There is no room between for the peculiar festooning 

 pattern that traverses the grooves in the other species. The 

 spiral bands of dark brown are narrower and more numerous 

 than in H. ventricosa. The lining is bright orange as is also the 

 reflected area of the columella. Length, 3 to 5 inches. 



Habitat. — Mauritius. 



The Noble Harp (//. nobilis, Lam.) is very distinct, its shell 

 much contracted toward the base, the spire elevated, the ribs 

 remote from each other, and painted with groups of fine black 

 lines, forming dark spiral bands. The broad sulci are painted 

 with curly lines of brown on a paler ground colour, or mottled 

 with dark spots on a rosy ground. Sometimes the rose tint is 

 restricted to large square spots. Length, 2 to 3 inches. 



Habitat. — Indian Ocean, Philippines. 



The Rose Harp (//. rosea, Lam.) is distinguished from its 

 near relative, H. nobilis, by its delicate rosy colour, the faintness 

 and irregularity of its flat ribs, and the absence of black cross 

 lines. Length, 2 to 3 inches. 



Habitat. — Senegal, Guinea. 



The Articulated Harp (//. articularis, Lam.) is ventricose, 

 thin and ashy gray, the distant ribs crossed by black spots or lines, 

 sometimes grouped. Faint festoons of gray and yellow occupy 

 about half of each wide interstice. Some forms are flushed with 

 pink over the gray colour scheme. Length, 2 to 4 inches. 



Habitat. — Pacific islands. 



The Crenated Harp (//. crenata, Swains.) has a scalloped 



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