THE COPEPODS OF THE WOODS HOLE REGION 

 MASSACHUSETTS 



'By Charles Branch Wilson 

 Department of Science, State Normal School, West field, Mass. 



INTRODUCTION 



LIMITS OF THE AREA STUDIED 



The Woods Hole region as considered in this report includes the 

 whole of Cape Cod, Mass., and all tlie islands south of it and those 

 portions of the surrounding ocean between latitude 40° and 42° N. 

 and between longitude 69° and 72° W. The area is thus approxi- 

 mately 200 miles wide and 150 miles long, and its limits have been de- 

 termined by the sources of the material upon which this bulletin is 

 based. Any reduction of the area would of necessity eliminate some 

 of the excellent material gathered during the earliest cruises of the 

 Fish Hawk and the Alhatross. As these were all included in the 

 notes and drawings made by Dr. Eichard Rathbun, it has been 

 deemed best to keep the collection intact. 



COPEPODS INCLUDED 



This report comprises a study of marine, brackish-water, and fresh- 

 water co^Depods — free-swimming, commensal, semiparasitic, and par- 

 asitic species. The region lies just at the latitude where the northern 

 and southern faunas meet and overlap. It contains, therefore, cope- 

 pod representatives of three distinct plankton faunas. The first of 

 these are the intrinsic species of the area itself, especially of the ponds 

 and the beach sands, and they constitute the great majority of the 

 present list. Then there are northern species, which have been 

 brought down by various currents from the Bay of Fundy, the 

 Gulf of St. Lawrence, or even farther north, and these make up the 

 list of northern stragglers. Finally there are southern species, 

 brought up fom the tropical Atlantic by the Gulf Stream, which 

 may properly be regarded as tropical visitors. 



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