LINNEAJSiT SOCIETY OF LOIfDON. 37 



captured in the two followiag years ; but in the spring of 1882 

 reports reached the Commissiou that vast numbers of this fish 

 were met with, dead aud floating over an area of more than two 

 degrees of latitude (between 38° and 40°) and four degrees of 

 longitude (between 70° and 73°). The cause of this mortality 

 has never been satisfactorily explained ; and since the year in 

 which this catastrophe happened no specimen of the fish has ever 

 been found. 



The work of the Commission was growing in every direction, 

 and as the ' Fishhawk ' proved to be too small for prolonged 

 cruises in the Grulf-Stream, a steamer of 1000 tons burden, the 

 ' Albatross,' with Lieut. Tanner as Commander, was added to the 

 fleet of the Commission. The work of this new steamer consisted 

 in 1883 in the exploration of the area between Lat. 35° and 45°, 

 Long. 61° and 77°, makiug a successful haul at a depth of 

 2949 fathoms ; the 1884 cruise extended southwards to the 

 Caribbean Sea aud Trinidad ; in 1885 from Halifax to Havana, 

 and in 1886 aud 1887 from the Bahamas to the Banks of New- 

 foundland. I find that in these five years the dredge or trawl 

 was used in deep water 476 times. 



But now the Deep-sea work of the Commission came practically 

 to an end. The work at more than 2000 stations had carried the 

 exploration to a point at which the ground had been sufiiciently 

 exlaausted to admit of attention being given to the claims of other 

 unexplored areas. The ' Albatross ' was ordered to proceed to 

 the Pacific coasts of the United States. 



During the progress of this work of the Fish Commission the 

 U.S. Coast Survey was active especially in somewhat lower 

 latitudes, but in 1880 they ordered their steamer ' Blake,' the 

 scientific work of which had been for some time uuder the 

 direction of Professor Alexander Agassiz, to engage in work 

 which falls iuto the area under consideration, and much on the 

 same ground which was already occupied by the Fish Commission. 

 The lines of observation were carried along and across the Grulf- 

 Stream between Lat. 32° and 47°. The Zoological collections of 

 the ' Fislihawk ' and ' Albatross ' were largely added to by this 

 cruise; but Prof. Agassiz made the formation of the sea- bottom, 

 the direction and strength of the currents, serial temperatures, 

 and the influence of these physical conditions upon the distri- 

 bution of animal life, the chief objects of his enquiry. The 

 southern portion of the Grulf-Stream was shown to pass over a 

 plateau with a moderate depth above it, extending to the latitude 

 of Charleston, and called the Blake Plateau. The current sweeps 

 this plateau clear of ooze aud nourishment, thus causing an 

 almost azoic condition of this part of the sea-bottom *. 



* ' Three Cruises of the U.S. Coast and Geodetic Survey Steamer ' Blake,' ' in 

 2 vols., 1888, 8\-o (also as vols. 14 aud 15 of Bull. Mas. Comp. Zool.). A 

 masterly general treatise of the results of these cruises and an important con- 

 tribution to almost all branches of Oceanography, dedicated to the memory of 

 L. F. Pourtales. 



