The Tritons and Frog Shells 



shelly material. This thickening of the lip precedes a period of 

 rest. When growth is resumed the mantle extends the shell 

 leaving the thickened lip behind as a varix crossing the whorl. 



The apex is peculiar in structure. It is horny with a thin 

 plating of shelly substance outside. The shellis often seen chip- 

 ped off, exposing the horny foundation. 



Triton's Trumpet {T. tritonis, Linn., T. variegatus. Lam.) is 

 called "the Variegated Triton," by Reeve. Variegated it is, 

 with buff, and brown, ,purple and red, in rich patterns suggesting 

 the plumage of pheasants. The ground is pale; the dark colours 

 are laid on in crescentic patches, no longer than the width of the 

 spiral ridge they ornament. The columella is dark purplish brown, 

 crossed by white wrinkles. The spire bears about a dozen flat 

 varices. The outer lip is toothed, and whitish, with double streaks 

 of brown soon fading into the ruddy aperture. The canal is 

 short and recurved. 



This is the giant Triton which reaches sixteen or eighteen 

 inches in length. The Pacific Islanders use it for a teakettle, 

 the operculum being the lid and the canal, the spout. The shell 

 is hung by a wooden hook over the fire. The long spire and 

 swollen body whorl give a sixteen-inch Triton considerable 

 capacity. 



Habitat. — New Zealand, Polynesia, Philippines, Japan, 

 Indian Ocean. 



Variety nobilis, Conr., differs from the type in being broader 

 and heavier, with a distinct shoulder, especially noticeable on the 

 body whorl. The first few coils of the spire are quite smooth. 

 The aperture is pale orange. The shoulder appears only on adult 

 shells. This is the West Indian Triton, found also in the Medi- 

 terranean and Cape Verde Islands. 



The Knobbed Triton (T. nodiferus, Lam.) is a big-mouthed, 

 stout trumpet shell, with a double ro\v of knobs encircling its spire. 

 Instead of becoming larger on the body whorl, the knobs fade out. 

 There are Tritons much more noticeably knobbed than this one. 

 The gaping throat has a pale lining. Brownish yellow tessela- 

 tions adorn the strongly ridged exterior and mark the toothed 

 lip border. The broad, brown columella is wrinkled dbove and 

 below. Length, 5 to lo inches. 



The species in somewhat variable forms occurs up the Atlantic 

 Coast of Europe to the British Channel, and South to the Canary 



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