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did Doctor McMurrich detect it at all at St. Andrews at that season, though it 
occurred there in November, December, and January, and occasionally in February 
and March. In fact, we have usually found it wanting in summer throughout the 
Fig. 49. — Occurrence of the euphausiid shrimp, Thysanoessa inermis, February to April, 1920. ®, occurred; O. none 
taken. The hatched curve incloses the area where it occurred in about 50 per cent of the stations for March and April 
coastal zone from Cape Cod to Grand Manan, with the 100-meter contour roughly 
marking its shoreward limit from Cape Ann to the mouth of the Grand Manan 
Channel at that season. But its regular presence over the shallow southern rim of 
