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bulletin: museum of compailvtive zoology. 



Eastern Basin, where the increase, at 200 meters, was about .6%o in 

 this period (33.8Sco to 34.4%o). 



We have no records of seasonal changes in the eastern half of the 

 Gulf after September; for our western stations, this has been discussed 

 (p. 206). 



Finally, I should point out that the water close to land, off Shel- 

 burne (Station 10313) was even fresher on the surface in September 



Meter 



Fig. 74. — Salinity profile across the continental shelf off Shelbume, Nova Scotia, 

 June 23. 1915 (Stations 10291-10295). 



than in June; but it was considerably Salter on the bottom; while a 

 few miles further offshore (Station 10314), salinity as a whole rose 

 considerably during the summer (Fig. 75, 76). 



The most important seasonal change in density in the Gulf is the 

 fact that the great vertical stability which characterizes the water 

 in summer, practically disappears, as the upper layers cool, in winter, 



