258 FARLOW— VEGETATION OF SARGASSO SEA. [April 24, 



" The Sargasso Sea of the North Atlantic covers a rather indefinite area 

 between 22.° and z(i° N. and according to the statements of the older navi- 

 gators, the amount of Sargassum to be met w^ith varies from occasional 

 patches to masses large enough to impede the progress of sailing vessels. 

 The Sargassum probably changes its position constantly, according to the 

 seasons, the currents, and the direction of the wind; but within the area 

 bounded by the Gulf Stream on the West, the equatorial current on the 

 South and the return current from the Azores and Canaries the Sargassum 

 has always been found in larger or smaller quantities." 



At the present day we have a definite knowledge of the ocean 

 currents and the prevailing winds of the Atlantic which are im- 

 portant factors in the distribution of the gulf-weed. My personal 

 experience, which has been confined to that part of the Ocean lying 

 between New York and Bermuda, agrees with that of most recent 

 travellers who have traversed the Sargasso Sea in various directions 

 and it may be said that the gulf-weed occurs in scattered patches 

 which are usually from fifty to, at the most, a few hundred feet in 

 diameter. It appears to be certain that in no place is the Sea covered 

 by the gulf-weed in continuous masses miles in extent and it is not 

 often the case that the patches extend over a space as large as an 

 acre. Their long diameter is usually in the direction of the wind 

 and their frequency varies very much according to circumstances. 

 Whether they are ever so dense as actually to impede modern sailing 

 vessels seems to me doubtful, and it must be said that those who 

 make the statement that the progress of vessels may be impeded by 

 the gulf-weed usually preface their remarks by saying * according to 

 older navigators ' and do not depend on their own observations. 



If at the present day we have a good topographical knowledge 

 of the Sargasso Sea, the question as to the particular species to 

 which the gulf-weed belongs still presents several perplexing prob- 

 lems and, as to the origin of the gulf-weed, as recently as 1907 

 Sauvageau wrote : " les causes de sa formation ne sont guere mieux 

 connues que lors du premier voyage de Christophe Colomb." Sar- 

 gassum, to which the gulf-weed, Sargassum haccijerum^ belongs is 



1 The name Sargassum bacciferum is used here since it has been the 

 name most commonly used to designate the gulf-weed. Boergesen in his 

 paper, " The species of Sargassum found along the coasts of the Danish 

 West Indies with Remarks upon the Floating Forms of the Sargasso Sea," 

 Copenhagen, 1914, states fully the reasons for preferring the name Sar- 

 gassum iiatans (L.) on the ground of priority. 



