Shell-Bearers 



Progress with these creatures is slow but sure. Some 

 of the molluscs are much more lively. The scallop, a 

 familiar object on the fishmonger's stall, with its pretty 

 shell and bright orange foot, swims rapidly in the water 

 with a zigzag movement by quickly opening and closing 

 the valves of its shell. While we are on the subject of 

 the scallop, let us notice another peculiarity in structure 

 by means of which the creature is ingeniously protected 

 from danger. The cockle will serve equally well as an 

 example if a scallop be not at hand. Despite their hard, 

 substantial, portable housesj all molluscs are fit food for 

 a number of hungry beasts, and ingenious beasts withal. 

 Some of their enemies pierce their shells, some dissolve 

 them, some break them, and some, catching the inmates 

 napping, force them open. There is one thing the 

 enemies of the cockle and scallop cannot do, and that is, 

 push one valve from another sideways, and for this reason : 

 the margins of the valves are wavy or toothed or serrate, 

 and the hollows of one valve fit into the raised portions 

 on the margins of the opposite valve. Willy-nilly some 

 of these bivalves display considerable ingenuity in 

 attempting to rid themselves of their enemies. 



The oyster is a type of stationary mollusc ; except in 

 its very young stages it never moves from the spot where 

 it first takes up its position. Those of us who eat these 

 so-called delicacies cannot fail to have noticed that the 

 left-hand valve is the larger and is curved, whilst the right- 

 hand valve is flat or nearly so. Quite early in life the 

 curved or lower valve becomes attached to a stone or 

 some other support, whilst the right or upper valve 

 remains free to open and close. Seeing that the oyster 

 is such an immobile creature, it is hardly necessary to add 

 that it has no foot. In our wanderings by the sea-shore 

 we may often have picked up the valve of an oyster shell 

 pitted and bored in all directions with a number of small 

 holes. 



Our find probably means little or nothing to us, but if 



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