560 



seems best to express the production of a body of water in vol- 

 ume per cubic meter. I have therefore used this basis through- 

 out my paper, and employ it in the following table of compara- 

 tive production in some of the representative bodies of water 

 thus far reported. 



RELATIVE PLANKTON PRODUCTION BASED UPON MAXIMUM RECORD. 





Locality 



Illinois River 



Spoon River 



Quiver Lake 



Dogfish Lake 



Flag Lake 



Thompson's Lake. 

 Phelps Lake 



Turkey Lake.. . 



Lake St. Clair.. 

 Lake Michigan. 



Investigator 



Kofoid 



Juday, (97) 



Reighard, (94) 

 Ward, ('95) 



Date 



3. 

 11, 



3, 



17, 



2 



1, 



V, 1 

 IX, 1 



V, 1 

 IV, 1 



V, 1896 



V, 1 



23, VIII, li 



\ 12, VIII, 18 

 I 12, VIII, 1896 



17, IX, 18 

 11, VIII, 18 



Depth 

 — in 



meters 



12 



2 



51 

 64 



5 

 2 



i-5 



6.09 



4-37 



107.8 



Plankton — in cm. 3 



Per sq. Per cu. rae- 

 meter ter. 



4I3-89 



60.11 



353-98 



102. 16 



667.55 



184.32 



89.79 



71.36 



14.59 



84.28 



40.70 



407.04 



122.88 



448.96. 



1439.5* 

 826.5* 



74.5 2 

 176.29 



135-5* 



17-05 



1.64 



Danube, backwaters. 

 Elbe, backwaters 



Steuer, ('01) 

 Schorler, (99) 



? 

 20, 



V, iE 



V, iE 



3-' 

 3-4 



16 

 438-584 



12. 

 146. 



Garda See 



Ploner See 



Ploner See 



Dobersdorfer See. 

 Navern See 



Sognsvandet See 



Waterneverstorfer See 



Lac Leman 



Vierwaldstiitter See 



Neuenburger See. 



Katzen See 



Sttihmer See 



Garbini, (95) 

 Zacharias, ('96) 

 Apstein, ('96) 

 Apstein, ('96) 

 Huitfeldt-Kaas, 



C98) 

 Huitfeldt-Kaas, 



('98) 

 Lemmermann, 



(98) 

 Jung, (99) 

 Burckhardt, 



(bob) 

 Fuhrmann, Coo) 

 Amberg, ('00) 

 Seligo, ('00) 



10, VIII, 1895 

 6, IX, 1892 

 4, X, 18 



50 

 40 

 17 

 19. 



3o(?), VI, 



18, VI, 1898 



? 

 27, V, 1899 

 14, XI, 1898 

 9, VIII, 1898! 



7 

 shallow 



2 

 120 



40 



5 



23 



62 



862 



1242 



4242 



520 



240 



7o 

 101 .9 



150. 



9i-3 

 6.2 

 2340 



1.24 

 21.55 



73-07 

 218.05 



74.29 



35- 



0.85 



2.24 



1.24 



101 .79 



*Reduced to settling method of measurement by multiplying by 5. See Juday (97). 

 fAU records for our stations reduced to settling method of measurement by multi- 

 plying by 2. See page 256. 



A comparison of this maximum production in these various 

 localities, upon the basis either of plankton per square or cubic 

 meter, ranks our localities (barring Spoon River) among the 

 more fertile regions. If the content per cubic meter be the ba- 



