8. Ovigerous females were relatively inactive 

 and, thus, less destructive of pelecypods than non- 

 ovigerous females. 



9. Feeding by crabs preparing for ecdysis and 

 subsequent hardening of the exoskeleton was gen- 

 erally reduced, except for crabs that had nearly 

 hard shells. 



10. Feeding of male crabs apparently is mark- 

 edly reduced during the mating act. 



ACKNOWLEDGMENTS 



Fenner A. Chace, Jr., Curator, Division of Ma- 

 rine Invertebrates, U.S. National Museum, pro- 

 vided the taxonomic background for the valid 

 generic name of the green crab, namely, Carclnus 

 rather than Carcinides. Lionel Sheppard, former 

 Clam Commissioner of Ipswich, Mass., assisted 

 during many of the dredge collections. Franklin C 

 Daiber of the Univereity of Delaware read the 

 manuscript and made helpful suggestions. 



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U.S. FISH AND WILDLIFE SERVICE 



