The Tritons and Ftog Shells 



in the genus, no doubt made a useful lamp for primitive man. 

 Its strong revolving ridges are elaborately set with nodules. The 

 flaring lip is deeply crenulated. There is a posterior channel 

 equal to the anterior canal. When half grown the shells are heavy 

 and show the adult characteristics. The creamy ground colour is 

 stained with orange brown; the aperture has a flesh tint. In young 

 shells the colours are brighter; the lip and aperture orange-red. 

 Length, 3 to 9 inches. 



Habitat.^ Red Sea, Indian Ocean, Philippines. 



The Argus Ranella (R. Argus, Gmel.) has an ovate, ven- 

 tricose shell with nodules of moderate size evenly distributed over 

 its surface, sometimes large and few, sometimes small and crowded. 

 The colourless surface is spirally banded with brown. The eyed 

 appearance is due to wearing off the brown on the nodules. The 

 thick lip is obscurely wrinkled inside, and often bears a tooth 

 at the edge of the anterior canal. 



This species feeds by night on the skeletons of seals left by 

 fishermen on the rocks on the Islands of Amsterdam and St. Paul 

 (Indian Ocean). A dead bird or a fish hung as bait over night 

 in water thirty or forty feet deep will capture them without fail. 

 Fresh specimens are covered with a brown, wrinkled epidermis. 

 Length, 2^ to 4 inches. 



Habitat. — Cape of Good Hope, Chili, Indian Ocean, New 

 Zealand. 



The Beautiful Ranella (R. pulchra, Gray) has its varices 

 prolonged into fan-like wings or fins, sculptured by ribs and 

 nodules. The whorls are rounded, the apex elevated, the white 

 aperture prolonged into a considerable canal. The lip and 

 columella are narrow and smooth. Length, i§ to 2i inches. 

 Colour, pale yellow mottled with pale brown. 



Habitat. — Japan, Philippines. 



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