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bulletin: museum of comparative zoology. 



depth, at the eastern than at the western side of the Gulf, down to 

 about 100 fathoms, equal salinities being found about 15-20 fathoms 

 deeper on the Massachusetts Bay than on the Nova Scotia side. 

 Below 100 fathoms there was much less variation in salinity from west 

 to east, depth for depth, the curve of 34%o following the 110 fathom 

 level right across the western basin. At 130 fathoms the salinity was 

 almost precisely the same (34.1%o) in the two basins. 



The water was much fresher at the mouth of Massachusetts Bay 



33.8%, 



Fig. 49. — Salinity profile from the trough between JefiPrey's Ledge and the 

 mainland (Station 10104) to the centre of the Gulf of Maine (Station 

 10090). 



than further east, especially at the bottom, while the very sudden dip 

 of the curve of 32.7%o suggests that vertical circulation was active in 

 the Bay. And this may well have been the case, as the tidal currents 

 are of some strength in the neighborhood of Station 10106. The 

 eastern end of the profile shows a sudden spreading of the curves over 

 the coast bank, such as we found in 1912 (1914a), the range of salinity 

 for the entire column of water on German Bank being only from 

 32.79%o-32.94%9. The only exception to the rule that salinity in- 

 creased from west to east is afforded by Station 10093, where the 



