454 D. J. SC0URF1ELD [june 1899 



the very considerable knowledge which we now possess about the 

 organisms constituting the plankton of fresh-water lakes — e.g. their 

 remarkable and often complicated variations in abundance during the 

 year, both collectively and taken species by species, their vertical dis- 

 tribution in regard to the season, to the time of day, to the so-called 

 " Sprungschicht," their occasional seasonal variation of form, their 

 relation to one another and to the other lake forms, notably the fishes, 

 — of all this and much more not one single fact has been contributed 

 by this country ! Who said " Shame " ? 



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