PLANKTON OF THE GULF OF MAINE 



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outnumbering it off Shelburne (station 10294) and on Browns Bank (station 10296) 

 during that month in 1915. 



With the advance of summer the ratio of bispinosa to compressa increases. 

 Thus, in July, 1914, bispinosa outnumbered the latter on the southern part of Georges 

 Bank (stations 10216 and 10223) and on Browns Bank (station 10228) and about 

 equalled it on the northwest part of Georges Bank (station 10215) and in the eastern 

 channel (station 10227) ; but compressa was still the dominant member of the pair 

 off Massachusetts Bay (station 10213), in the southeastern part of the basin of the 

 gulf (station 10225), over the northeastern edge of Georges Bank (station 10226), 

 along the continental edge off the southeast and southwest slopes of Georges Bank 

 (stations 10220 and 10218), and abreast of Shelburne, Nova Scotia (station 10233). 



In August of that year bispinosa was the dominant member of the pair near 

 Cape Sable (station 10243) and in the eastern side of the basin (stations 10245 and 

 10249). The two species were about equal off Mount Desert and Penobscot Bay 

 (stations 10248 and 10250). In the deep water off Cape Ann (station 10254) com- 

 pressa was the more numerous at the surface, but bispmosa predominated in the 

 haul from 225-0 meters. Compressa still dominated at the mouth of Massachusetts 

 Bay and in the south central parts of the basin (stations 10253, 10255, and 10256), 

 but bispinosa was much the more numerous of the two at two stations on the conti- 

 nental shelf off Marthas Vineyard at this time (stations 10258 and 10259), and while 

 it dominated at one station at the continental edge (station 10260), compressa out- 

 numbered it at another station a few miles farther out (station 10261). 



Bispinosa is not so important, relatively, in the inner parts of the gulf every 

 summer, for in 1913 compressa outnumbered it at all the August stations east of 

 Cape Cod and north of Georges Bank, though bispinosa was more plentiful then 

 than it had been a month previous (we have no autumn records for that year in 

 the gulf), and with the same center of abundance as in 1914 — that is, the central 

 and eastern parts of the deep basin. Bispinosa outnumbered compressa in Massa- 

 chusetts Bay, off Cape Cod, and locally south of Marthas Vineyard in October, 

 1915 (stations 10258 to 10267); and in the first week of November, 1916, it again 

 predominated off Cape Cod (station 10404) but was detected at only two of five 

 stations farther north in the guff at this time, whereas compressa was at all of them. 

 Compressa was also the only Euthemisto noted close to land near Marthas Vineyard 



