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bulletin: museum of comparative zoology. 



western slope of Jeffrey's Bank. But it gradually receded from the 

 surface, passing toward the northeast, the curve of 42° dipping from 

 thirty fathoms at Station 10087 to forty fathoms at Station 10089, 

 and to the bottom, in about sixty fathoms, on the slope of the Bank. 

 And there was no water as cold as 42° on the northeast side of the 

 bank. Whether the 42° water was underlaid by warmer water in the 



Fig. 22. — Temperature profile running northeastward from off Cape Ann 

 (Station 10087) toward Piatt's Bank to Station 10089. 



northern end of the western basin, as it was further south (Station 

 10088), is uncertain; but this was probably the case. 



Profiles running off shore from the western side of the Gulf further 

 delimit the 42° water. The first of these, from the trough between 

 Jeffrey's Ledge and the mainland (Station 10104) to the centre of the 



