G-PLANKTOMC STUDIES: A COMPARATIVE INVESTIGATION 

 OF THE IMPORTANCE xVND CONSTITUTION OF THE PELAGIC 

 FAUNA AND FLORA. 



By Ernst H.eckel. 

 [Trauslated hy George Wilton Field.] 



TRANSLATOR'S PREFACE. 



Prof. Haeckers " Plankton Stiulien " first appeared in the Jenaische 

 Zeitschrift., vol. XXV, first and second parts, 1890. It was immediately 

 published in separate form by Gustav Fischer, of Jena, and attracted 

 much attention on the Continent and in England. The subject, "a 

 comi)arative study of the importance and constitution of the marine 

 fauna and flora," is presented in Prof. HiTeckel's usual pleasino- style, 

 and the work can not fail to be of value to all interested in the bio- 

 logical sciences, to the general reader as well as to the specialist. It 

 derives especial interest in connection with the work of the Fish Com- 

 mission, from its broad discussion of those many important elements 

 which enter into the food supply of all pelagic fishes, such as the 

 mackerel and menhaden, and, considering the extensive physical inves- 

 tigations now being conducted in our coast waters by the schooner 

 Granipiis, its publication at the present time will prove exceedingly 

 advantageous. 



The terminology used by Prof. Haeckel may at first seem formidable, 

 but this difficulty is more fancied than real. The ^terms are formed 

 upon correct analogies, and most of them will probably find a perma- 

 nent place. The definite restriction of the meaning of terms is a funda- 

 mental necessity in every science, and for the lack of this the branch 

 of biology here considered is in a very unsatisfactory condition. The 

 author, first of all, proposes certain terms with a definite meaning. 

 The word "plankton," from the Greek -Xayxro^, wandering, roaming, was, 

 I believe, first employed by Hensen in j^lace of the German "Auftrieb," 

 to designate all plants and animals found at the surface of the ocean 

 which are carried about involuntarily in the water. Hteckel adopts this 

 term, but objects somewhat to the meaning at present attached to it. 



Particularly valuable for us is the general review which the author 

 gives of the discovery and growth of our knowledge of this branch, 



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