MUSEUM OF COMPARATIVE ZOOLOGY. 363 



No. 13. — Report upon Deep-Sea Dredgings in the Gulf Stream, 

 during the Third (raise of the IT. S. Steamer Bibb, adJres.-oil 

 to Professor Benjamin Peirce, Superintendent U. S. Coast 

 Survey, by Louis Agassiz. 



(Communicated uy Professor Peirce.) 



The survey of the Gulf Stream, including soundings and dredgings 

 in deep waters, had been going on for two years under your direction, 

 when I was invited by you to join a third cruise. The surveying party 

 this year, as before, was accommodated on board the United States Coast 

 Survey steamer Bibb, master commanding Robert Piatt, who had charge 

 of the hydrographic survey, while Assistant L. F. Pourtales, who had 

 hitherto superintended the dredging operations, still continued to direct 

 the same work. The object of my own connection with the present 

 cruise was to ascertain how far the last investigations covered the 

 ground to be surveyed, and to what extent and in what direction 

 further researches of the kind were desirable in the same region, and 

 likely to furnish important information. The work of M. Pourtales 

 had been so eminently successful, the results obtained in this short time 

 so unexpected and of such high scientific value, that little more than 

 a repetition, or perhaps, in some respects, a modification of his results 

 could be expected from my participation in this year's operations. 

 It is a pleasure for me to state that our cruise — extending farther 

 to the east in the Gulf Stream, between Cuba and the Bahamas on one 

 side and Florida on the other, than those of previous years — confirmed 

 in every feature the conclusions already reached by M. Pourtales. His 

 results may therefore be considered as settled facts, deserving the fullest 

 confidence of the scientific world, and requiring only, in order to obtain 

 the appreciation they deserve, that kind of publicity which illustrated de- 

 scription-; and maps can give them. When thus made known, it will be seen 

 that we owe to the Coast Survey the first broad and comprehensive basis 

 for an exploration of the sea-bottom on a large scale, opening a new era 

 in zoological and geological research. I speak thus emphatically, be- 

 cause the data hitherto obtained concerning the animals of the deep 

 sea have been rather isolated, and not methodically connected with one 



