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 O 



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20 liJ 

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10 15 

 MINUTES 



Fig. 3. The burrowing^ ability of juvenile clams of various sizes 



exposed to a cuiVent velocity of 18 cm. per second. Solid 

 circles — Cumulative percentage of clams which burrowed. 

 Open circles — CuF.ulative percentage of clams washed into 

 sediment trap and^ therefore unable to burrow. The corres- 

 ponding size groups together with the inactive clams (not 

 represented) total 100^ at any given time. 



