16 Mindeskrift for J. Steenstrup. XXXII. 



immense bank from wliicli the supply of Snrgassuin is constantly derived; but such a bank, 

 if covered by only as much water as the greatest depth at which any Fucaoeous plant is 

 known to grow, could scarcely have escaped the notice of voyagers. And the aspect of this 

 Sargassum, with its innumerable floating-bladders, shews that it was not intended to vegetate 

 at any great depth; for \ve invariably find the air-vessels most numeroiis in species which rise 

 to the surface, and altogether absent in those which are deeply submerged." 



As may be seen from this quotation, Harvey gives a very clear representatioii 

 of the mode of living and of the origin of the Sargassum, at the same time as he 

 protests against the supposition of Alex. von Humboldt ') that the Gulfweed should 

 originate from immense submersed banks. 



Earlier than Harvey various authors have expressed the same opinion. Meyen in 

 Reise um dieErde, IsterTheil, p. 39 says: "Nach unserer Meinung schwimmen sie (the Gulf- 

 weed) an dem Orte ihres Vorkommens vielleicht schon seit Tausenden von Jahren." 

 Moreover Robert Brown ^) referring especially to Meyen's observations expresses his 

 view in the same way: 



"That the Gulfweed of the great band is propagated solely by lateral or axillary rami- 



fication, and that in this way it may have extended over the immense space it now occupies, 

 is highly probable, and perhaps may be affirmed absolutely without involving the question of 

 origin, which I consider as still doubtful." 



But, as already mentioned, the bulk of recent litterature') treats the floating 5ar- 

 gassum as an alga torn loose from the coasts of the West Indies and America, a con- 

 clusion that has probably been reached through the discussion of Otto Kuntze ' ). 



') Alex. von Humboldt und A. Bo^plandt, Reise in die Aequinoctial-Gegenden des neuen 

 Continents, Ister Theil, 1815, p. 3U5. 



-) Robert Brown, On the Origin and Mode of Propagation of the Gulf-weed in "Proceedings 

 of the Linnean Society of London", Vol. II, 1855, p. 77. 



') Besides the works already quoted compare also: 



Thoulet, i., l'Océan, ses lois et ses problémes, Paris 1904, p. 367. 



Oltmanns, F., Morphologie und Biologie der Algen, 2ter Bd., 1905, p. 171. 



Schott, g., Geographie des Atlantischen Ozeans, 1912, p. 268 (concerning the Sargassum in 

 the Sargasso Sea is said here: "Hier mogen sie mehrere Jahre sich halten, ehe sie allmåhlich 

 absterbend zur Tiefe sinken"). 



Neger, Fr. W., Biologie der Pllanzen, 191:?, ]i. 277. 



ScHENCK, H., in the newesl editions of "Lchrbuch der Botanik" on the other hånd siipporls 

 the view of Sauvageau (1. c). 



*) The paper of Kuntze (in Engler's Bot. Jahrbucher, vol. 1, ISKl) intends to show that 

 Sargassum natans is no valid species and that the Sargasso Sea is a mere myth. In reference to 

 this I can not abstain from reprinting some of his assertions viz.: "Der name natans schliesst 

 nun bereits einen Irrthum in sich; leider glaubte Linné den herrschenden Ansichten und un- 

 wissenschaftlichen Berichten friiherer Seefahrer mehr, als den exacten Beobachtungen des chr- 

 wiirdigen Botanilærs Rumphius". Turner is claimed to be: "Der eigentliclie Begriinder dicser 

 vermeintlicher Art". And about the floating Gulfweed is said: "Aber sowie man einen ins 

 VVasserglas gesteliten, kurze Zeit weiter vegetirenden Blumenzvveig nicht eine Wasserpflanze nennt. 



