BIGELOW: EXPLOKATKJXS OF THE COAST WATERS. 



31!) 



The copepod population of the Gulf for May differs from that of 

 midsummer chiefly in greater local variation, the rich regions being 

 richer, the barren ones even more barren. Thus, the range, was 

 from 1000-500,000 per square meter in May; from 17000-1S9000 

 in July and August 1913; 27000-123000 in August 1914. Probably 

 this is a regular seasonal phenomenon, for in 1915 local differences 

 were much smaller in autunm, the number of copepods decreasing 

 in the rich, increasing in the barren portions of the Gulf during the 

 summer. Thus the extraordinarily dense copepod population of the 

 waters oif Cape Ann dwindled from 500,000 per square meter early in 

 May, to about 50,000 at the end of August, rising again to 112,000 

 in October. The swarm over the eastern part of the Eastern Basin 

 underwent a similar change, diminishing from about 400,000 per 

 square meter in May (Station 10270) to about 114,000 in September 

 (Station 10310). , 



