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This is not all. The same conception, or should it be called a mis- 

 conception, is to be found, expressed more cautiously perhaps, not 

 only in the technical writings, textbooks, and laboratory manuals, 

 but also in most of the semipopular books and reference books that 

 treat plankton organisms to any extent whatsoever. To cite but three 

 instances: Hickson (1893, p. 52), in his Fauna of the deep sea, says: 

 "Some animals simply float or drift about with the currents of the 

 sea and are unable to determine for themselves, excepting, perhaps, 

 within very small limits, the direction in which they travel. . . . This 

 portion of the fauna has recently been called the Plankton." Again, 

 Arnold (1903, p. 23) in her Sea-leach at ehh-tide, says: "Those 

 [organisms] which float at or near the surface and are carried about 

 by the currents . . . are plankton. Strong swimming animals which 

 move about at will are nekton." Finally, on page 702 of the New 

 International Encyclopaedia (1916), one finds this statement: "In 

 zoology the term [plankton] is restricted to the pelagic life which 

 drifts, the actively swimming surface forms constituting a separate 

 assemblage, the nekton. It consists mainly of jelly fishes, ascidians, 

 especially salpa, and a great variety of pelagic larvae and minute 

 Crustacea with feeble powers of locomotion that are carried along 

 almost passively by the oceanic currents. ' ' 



This list of quotations might be continued almost indefinitely. All 

 carry the implication, some more conspicuously than others, that 

 plankton organisms, because of their feeble powers of locomotion, 

 may be assumed to behave like corks; that the characteristic quality 

 of such organisms is to float, to drift, to remain in suspension. It 

 may be, perhaps, that few actually believe this ; it is difficult to under- 

 stand how anyone can believe it. Yet, the above list of quotations 

 makes it certain that it is precisely this ridiculous assumption that 

 lies at the foundation of the prevailing plankton concept ; that it 

 colors the thinking of able biologists ; and that it influences the pro- 

 cedure of capable investigators. 



There are, to be sure, a few text books, a few reference books, a 

 few semipopular books treating of plankton that are not permeated 

 by this dogma, but the number is remarkably small. On page 309 

 of Murray and Hjort's Depths of the ocean (1912), this statement 

 occurs : ' ' The term ' plankton ' is now used for all floating organisms 

 which are passively carried along by currents, while 'nekton' . . . 

 is used to designate all pelagic animals which are able to swim against 

 currents." Although this statement carries the same implication, 



