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bulletin: museum of comparative zoology. 



The one station (18) made off Boon Island near the end of April 

 (April 25, fig. 5) is especially interesting because the water proved to 

 be considerably Salter (surface 31.76%o, 15 fathoms, 32.46%o; 30 

 fathoms, 32.65% o) at the surface, and down to about 15 fathoms than 

 the Isles of Shoals stations the day before or the day after, though 

 below 15 fathoms its curve agrees almost exactly with the latter. 



Fig. 7. — Siirface temperature • 



and surface salinity, , near 



Boon Island, April 1-14, and near the Isles of Shoals, April 16-May 16 



And inasmuch as there is no reason to assume any upwelling, the 

 weather having been calm for the two preceding days, it is safe to 

 conclude that the surface water was normally Salter a few miles north 

 of Boon Island than it was near the Isles of Shoals. 



The Wood Island ground was visited April 9, 10, and 14. On the 

 9th, the temperature was practically equalized at 39° from surface to 

 bottom, just as it had been off Boon Island four days earlier; and by 



