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bulletin: museum of comparative zoology. 



being only .2%o; and in the Grand Manan Channel (Station 33) there 

 was virtually no difference in salinity at different depths, i. c, we find a 

 reproduction of the temperature curve, though at all depths it was 

 somewhat fresher than the water over German Bank. 



Salinity at twenty-five fathoms (Plate 2). — We have only a few 

 samples at precisely this depth; but the salinity sections, and samples 

 taken at several stations a little deeper or a little shallower than 



Fig. 26. — Salinity sections at Stations 9, 11, 15, 19, 21, from Ipswich Bay to 

 Monhegan. 



twentj'-five fathoms, afford sufficient data for tentative mapping of the 

 curves for the various values at this level. It must be remembered, 

 however, that it, and the following charts, are not offered as final. 

 At twenty-five fathoms the salinity for the whole of Massachusetts 

 Bay, and for an area extending eastward some thirty miles over part 

 of the deep basin was between 32.5 and 32.6. A^d comparison with 

 the chart of surface salinity (Plate 1) shows that the curve of 32.6 in 

 this region reproduces the eastward swing of the curves of 31.8 and 



