428 



THE OCEAN WOELD. 



The fourth family, Bvccinidaz, contains numerous genera, as 

 examples of which we may instance Oliva, Harpa, Cassis, Purpura, 

 Nassa, Terebra, Hburna, and Buccinum. 



Oliva is so named from their resemblance in form to the olive. 

 Their nearly cylindrical shell is slightly spiral, polished, and brilliant 

 as the Cowries ; its opening is still long and narrow, strongly notched 

 in front, its edge columellar, swollen anteriorly into a kind of cushion, 

 and striped obliquely in all its length. 



These Molluscs belong to the seas of warm countries, where they fre- 

 quent the sandy bottoms and clear waters. They creep about with much 

 agility, reversing themselves quickly when they have been overturned ; 

 they live upon other animals, and are flesh-eaters. They are, in fact, 

 taken at the Isle of Tranu by using flesh as bait. The colours of the 

 shell are very varied, and sometimes fantastically streaked. Oliva 

 erythrostoma (Fig. 267) is ornamented externally with flexual lines of 



Fig. 267. Oliva Fig. 268. Oliva por- 



erythrostoma (Lamarck). pkyria (Linnasus). 



Fig. 269. Oliva iri- 

 sans (Lamarck). 



Fig. 270. Oliva Peru- 

 viana (Lamarck). 



a yellowish brown, with two brown bands, combined with the fine 

 yellowish tint of gold colour within. Oliva porphyria, from the 

 Brazil coast (Fig. 268), presents lines of a reddish brown, regularly 

 interlaced with spotted large brown marks, upon a flesh-coloured 

 ground. Oliva irisans (Fig. 269) is painted in zigzag lines, close 

 and brown, edged with orange-yellow, and with two zones of darker 

 brown, and reticulated. Oliva Peruviana (Fig. 270) is furrowed with 

 regularly spaced bands. 



