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bulletin: museum of compakative zoology. 



Salinity, Cape Cod to Chesapeake Bay. 



1. Surface salinity. The surface salinity (Plate 2) from Cape Cod 

 to the southern edge of Nantucket Shoals was 32.2%o-32.6%o. And 

 the record of 32.3%o at the eastern end of Vineyard Sound agrees so 

 well with Sumner, Osburn, and Cole's (1913) records for the surface 

 waters of that region in August, 1906 (32.2%o to 32.3%o) that we can 



Fig. 29. — Temperature profile lengthwise of the northeastern part of the 

 basin from south to north (Stations 10093, 10097). For 42° read 42.5°. 



assume^that value as normal for summer. The few stations in this 

 region suggest that the curve of 32.3%o swings westward toward the 

 mouth of Vineyard Sound, which agrees with their statement (1913, 

 p. 36) that there is a dominant westerly movement of the water 

 through the Sound of about two knots per day. 



From Nantucket light-ship out to the edge of the continental shelf 

 there was a steady, and fairly uniform rise in salinity to about 33.4%o 



