TROCHUS TOP SHELL. 99 



nated* at the suture ; columellar lip grooved, 

 beak short and ascending ; colour whitish, orna- 

 mented on the ribs with parallel curved reddish 

 brown spots, which are shaded off to wards each 

 other ; columellar lip striped with dark brown ; 

 the length is a foot, sometimes sixteen inches, 

 and the breadth about half as much. 



It inhabits the Asiatic seas, and those of the 

 Torrid zone in general. It is used by the na- 

 tives of New Zealand as a musical instrument, 

 and by the Africans as a military trumpet. It is 

 supposed to be the shell intended by Ovid, when 

 he describes the waters of the deluge retiring on 

 the sound of the trumpet of Triton. 



GENUS TROCHUS.t 



TOP SHELL. 



Generic character. Shell univalve, spirally 

 convoluted ; form more or less conical ; aperture 

 entire, quadrangular, sometimes approaching to 

 round, generally wider than it is long ; margins 

 separated ; columella oblique. 



* Crenated, being notched, from the Latin cren o, the notch 

 an arrow, 

 off Plate IV. figures 4, 5, 6. 



