PLANKTON OF THE GULF OF MAINE 
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Passamaquoddy Bay closely parallels Massachusetts Bay, for Saggittre do not appear 
at all in Doctor McMurrich’s plankton lists for St. Andrews between the first week 
in April and the first week in June. Our spring cruises in 1915 and 1920 suggest 
Fio. 87. — Numbers of Sagitta elegans per square meter of sea area in March, April, and May, as calculated from the vertical 
hauls. O. less than 50, including stations where none were taken in the verticals; ©, 50 to 400; •, 400 to 1,000; 9, 
1,000+; stations where the horizontal haul yielded a swarm, but where no vertical haul was made 
that the stock of S. elegans is at its lowest ebb over the inner parts of the gulf as a 
whole at about the same season (that is, end of April and beginning of May) as it is 
in Massachusetts and Passamaquoddy Bays (fig. 87) but does not fall to so low an 
