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BULLETIN OP THE BUREAU OF FISHERIES 
propagation or of invasion (probably of the latter, judging from the scarcity of the 
species in the preceding February, as shown in the table on p. 299); but the rich 
gatherings of M. Tonga made there during August, September, and October, 1915, 
Fig. 75.— Occurrence of the copepod Metridia longa. ®, locality records, August to January; X. February to June. The 
hatched curve incloses the area where it has been found in summer and autumn 
are the clearest evidence, short of the actual discovery of breeding adults and of 
young stages, that active reproduction had been taking place locally, because there 
was nothing in the plankton in general, in the salinity, or in the temperatures of that 
