56 bulletin: museum op comparative zoology. 



easterly along the coast from Cape Ann toward the Bay of Fundy show 

 a similar rise of bottom temperature, irrespective of depth. Thus at 

 Station 11, in sixty fathoms, abreast of Portsmouth, the bottom read- 

 ing was about 40.3°; at Station 19, abreast of Cape Elizabeth, in fifty 

 fathoms, 42.3°; Station 39, off the mouth of Penobscot Bay, eighty 

 fathoms, 46°; Station 35, in the mouth of the Grand Manan Channel, 

 forty-five fathoms, 49.3°; which was only about 1° lower than the 

 surface temperature. 



Temperature 'profiles. — The first profile (fig. 16) constructed from 

 the temperature curves, shows the distribution of temperature for 

 July and early August from Boston to Station 29, on German Bank, 

 passing through Jeffrey's Bank, (Stations 6, 2, 7, 24, 25, 27, 28, 

 29). At the western end of the profile, there is a very thin surface 

 layer of warm water with temperatures above 46° overlying the cold 

 bottom water with a temperature of 40.3°-41°, which fills all the east- 

 ern basin below about forty fathoms. Passing eastward the lower 

 limit of the warm layer, which may be established arbitrarily by the 

 isothermobath of 46°, dips from about five fathoms at Station 6 to 

 fifteen fathoms at Station 2 ; and in the trough west of Jeffrey's Ledge, 

 it lies at about that same depth. From Station 2 to Station 7 it dips 

 to about twenty fathoms, which level it follows to Stations 23 and 24. 



At Station 25 a very interesting phenomenon is seen, for here the 

 curves for temperatures above 48° rise nearly to the surface, while 

 that of 46° touches the slope of Jeffrey's Bank at about seventy 

 fathoms. East of the bank the reverse occurs, the curve of 48° rising 

 to about fifteen fathoms at Stations 27 and 28, the curve of 46° to 

 twenty - twenty-five fathoms at these same stations. At Station 

 29 there is a distortion of the curves parallel to that on Jeffrey's Bank 

 (Station 25) ; the temperature of the entire water-mass being between 

 49.1° and 50.6°. 



Over the eastern part of the profile, the bottom water is less uni- 

 form in temperature than it is in the western, the coldest water (about 

 43°) being met on the eastern face of the slope of Jeffrey's Bank, while 

 the easterly part of the basin below thirty fathoms is filled with water 

 of about 45.3°. 



A profile from the basin (Station 28) to German Bank (Station 29) 

 passing through Station 31 (fig. 17) reveals the presence of a mass of 

 warm water on the surface at the latter. Over the first part of this 

 line the curves for temperatures between 46° and 54° dip sharply, the 

 former descending from about twenty-two fathoms at Station 28 to 

 about sixty-five fathoms at Station 31. The curve for 50° dips from 



