306 THE INHABITANTS OF THE SEA. 



be badly off indeed if they could not entirely conceal themselves 

 within their thick shells, and keep them closed by strong 

 muscular contraction. 



Bernardin de St. Pierre, in his " Studies of Nature," points 

 out another admirable provision for the safety of molluscs. 

 Thus, those -which crawl and travel, and can consequently choose 

 their own asylums, are in general those of the richest colours. 

 Such, among the Grasteropods, are the gaudily-tinted Nerites, 

 and the polished marbled Cowries, the Olives, richly ornamented 

 ivith three or four colours, and the Harps, which have tints as 

 rich as the most beautiful tulips ; while among the bivalves the 

 vivacious Pectens, coloured scarlet and orange, and a host of 

 other travelling shells, are impressed with the most lively colours. 

 But those which do not swim, as the Oysters, which are adherent 

 always to the same rocks, or those which are perpetually at 

 anchor, as the Pinnas and Mussels, or those which repose on the 

 bosom of Madrepores, such as the Arcs, or those which are 

 entirely buried in the calcareous rocks, as the Lithodomi, or 

 those which immovably, by reason of their weight, pave the sur- 

 face of the reefs, as the Tridacna, are of the colour of the bottoms 

 or floors which they respectively inhabit, in order, no doubt, 

 -that they shall be less perceived by their enemies. 



But even so the best guarded of the bivalves fall a prey to 



innumerable enemies, and when we see the strand covered for 



miles and miles with their debris, we may rest assured that but 



few of the quondam inmates of these fragmentary shells have 



died a natural death. Annelides and Sea-snails, crustaceans 



and star-fishes, strand birds and even quadrupeds, all fatten 



upon their deHcate flesh, and man devours incalculable numbers. 



In vain the Pholas buries itself in stone, or the cockle in the 



sand; their security was at an end as soon as man had found 



■out that they were grateful to the palate. The former was 



reckoned a delicacy by the ancients, and 



the latter is preferred by some to the oyster 



itself. So much is certain, that, during 



the years of famine caused by the potato 



disease, it preserved the lives of many of 



the poor Shetlanders and Orcadians. 



The Razor-Shells, particularly when 



roasted, and the Clam-Mussels, which are not only a favourite 



