PLANKTON OF THE GULF OF MAINE 



169 



1915 (station 10288) as at a near-by location (station 10270) on May 6, it seems that 

 the swarm resulting from this local center of active reproduction had dispersed in the 

 interim. Unfortunately no vertical hauls were made later than June in the summer of 

 1915, but in Jul} 7 and August, 1914, the average number of copepods per square meter 

 for the gulf, as a whole, inside the continental edge but including the offshore banks, 

 was between 72,000 and 73,000 (see Bigelow, 1917, p. 315, for table of counts) — i. e., 

 something less than half the May average for 1915, with a maximum of 227,000 in the 

 northern channel and a minimum of 6,000 on the northern edge of Georges Bank 

 at this time. 



Copepods were then most numerous per square meter (70,000 + ) in four distinct 

 regions as follows: (1) Over a V-shaped area, with one arm extending from Cape Cod 



Fig. 57. — Number of copepods per square meter of sea area, July and August, 1914, as calculated from the catches of the 

 vertical hauls. 1, scanty (less than 20,000); 2, intermediate (20,000 to 70,000); 4, rich (70,000 to 150,000); 6, very rich 

 (150,000 or more). Reproduced from Bigelow, 1917, fig. 94. 



toward Penobscot Bay, the other to the eastern part of Georges Bank; (2) off Cape 

 Sable; (3) in the extreme northeast corner of the basin of the gulf; and (4) south 

 of Marthas Vineyard (fig. 57). The maxima were off Cape Cod, off Cape Sable, 

 and in the northern channel (stations 10213, 10243, and 10229; Bigelow, 1917, p. 316). 

 On the other hand, we have found very few copepods in the coastal zone in the ex- 

 treme northeast corner of the gulf, in the southeastern part of the basin, in the eastern 

 channel, or in the oceanic water outside the edge of the continent during the summer. 

 The distribution of copepods on the basis of numbers per cubic meter has paralleled 

 this, except that the region northeast of Cape Cod was shown to be relatively less 

 productive by this than by the other calculation in July, 1914. The numbers per 



