10 MANUAL OP THE MOLLtJSCA. 



and cuttles, wlio vindicate their high position in the naturalists' 

 " system," by preying even on fishes. 



As the shell-fish are great eaters, so in their turn they afford 

 food to many other creatures ; fulfilling the universal law of 

 eating and being eaten. Civilised man still swallows the 

 oyster, although snails are no longer reckoned "a dainty dish;" 

 mussel, cockles, and periwinkles are in great esteem with 

 children and the other unsophisticated classes of society ; and 

 so are scallops and the haliotia, where they can be obtained. 

 Two kinds of whelk are brought to the London market in great 

 quantities; and the arms of the cuttle-fish are eaten by the 

 Neapolitans, and also by the East Indians and Malays. In 

 seasons of scarcity, vast quantities of shell-fish are consumed 

 by the poor inhabitants of the Scotch and Irish coasts.* Still 

 more are regularly collected for bait; the calamary is much 

 used in the cod-fishery, off Newfoundland, and the limpet and 

 whelk on our own coasts. 



Many wild animals feed on shell -fish ; the rat and the raccoon 

 seek for them on the sea-shore when pressed by hunger ; the 

 South American otter, and the crab- eating opossum constantly 

 resort to salt-marshes, and the sea, in order to prey on the 

 moUusca ; the great whale lives habitually on the small floating 

 pteropods ; sea-fowl search for the littoral species at every 

 ebbing tide; whilst, in their own element, the marine kind 

 are perpetually devoured by fishes. The haddock is a ''great 

 conchologist ; " and some rare northern sea-shells have been 

 rescued, unbroken, from the stomach of the cod ; whilst even 

 the strong valves of the cyprina are not proof against the teeth 

 of the cat-fish {anarhicas). 



They even fall a prey to animals much their inferiors in 

 sagacity ; the star-fish swallows the small bivalve entire, and 

 dissolves the animal out of its shell; and the bubble-shell 

 {philine), itself predacious, is eaten both by star-fish and sea- 

 anemone {actinia). 



The land-snails afford food to many birds, especially to the 

 thrush tribe; and to some insects, for the luminous larva of 

 the glow-worm lives on them, and some of the large predacious 

 beetles (e.g., carahus violaceua apd goerius olens), occasionally 

 kill slugs. 



The greatest enemies of the moUusca, however, are those of 



* See Hugh Miller's " Scenes and Legends of the North of Scotland." The KJok^ 

 kenmbdings, or kitchen refuse-heaps, which have been found so abundantly in Den- 

 mark, Scotland, New Zealand, and elsewhere, are sometimes hundreds of yai-ds in 

 length, and composed almost entirely of shells. 



