194 



PLANKTON OF WISCONSIN LAKES 



Table 23. The amount of ash and silt in the nannoplanhton of Lake 

 Mendota given in terms of milligrams per cubic meter of water. The 

 last part of the tahle shows four constituents of the ash stated in per- 

 centages of the dry weight of the nannoplankton. 



Number 



of 

 Sample 



529-31 

 535-37 

 541-45 

 549-51 

 553-57 

 561-65 

 567-75 

 579-81 

 585 

 589 



595-100 

 5102-6 

 5110-12 

 5116-22 

 5124-26 

 646-52 

 654-56 

 668-74 

 688-92 

 694-98 

 6100-6 

 6108-12 

 6114-18 

 6120-24 

 702 

 706 



Date 



June 8-11, 1915 

 June 14-17 

 June 21-24 

 June 28- July 1 

 July 6-9 

 July 12-15 

 July 19-22 

 July 26-29 

 August 2 

 August 6 

 August 9-12 

 August 16-19 

 August 23-26 

 Aug. 30-Sept. 2 

 September 7-9 

 June 12-16, 1916 

 June 19-22 

 July 5-7 

 July 24-28 

 July 31-Aug. 3 

 August 7-9 

 August 14-18 

 August 22-25 

 August 28-31 

 Jan. 18, 1917 

 March 9 



Total 



Ash, 



Mg. per 



Cu.M. 



926.6 



964.7 



727.9 



727.9 



921.6 



822.6 



1,260.8 



1,525.7 



1,404.0 



1,342.6 



678.2 



532.6 



588.5 



741.0 



503.0 



1,371.0 



1,577.7 



1,696.2 



1,767.8 



1,466.9 



1,454.7 



1,320.6 



1,297.0 



1,269.0 



1,155.6 



942.5 



Bowl 



Ash, 



Mg. 



per 



Cu.M. 



555.3 

 557.4 

 554.0 

 555.6 

 556.0 

 649.3 

 566.0 

 556.7 

 550.0 

 761.6 

 720.0 



Ash of 

 Nanno- 

 plankton 

 Mg. per 

 Cu. M. 



210.0 



192.3 



123.0 



133.4 



141.0 



158.5 



198.5 



176.7 



186.4 



232.0 



117.0 



105.0 



123.0 



154.2 



133.4 



117.0 



164.6 



248.1 



204.0 



174.0 



138 



161 



130 



124 



158 



111 



Silt, 



Mg. 



per 



Cu.M. 



710 

 772 

 604 

 594 

 780 

 664 

 1 ,062 

 1 ,349 

 1,217 

 1,110 

 561 

 427 

 465 

 586 

 369 

 698 

 855 

 894 

 1,008 

 736 

 667 

 593 

 610 

 594 

 235 

 112 



SiOs, 



Per 



Cent 



19.50 



20.91 



24.51 



21.92 



19. 7C 



17.72 



10.44 



6.35 



8.33 



11.32 



13.61 



13. 3o 



25.5? 



17.04 



14.71 



21. 7C 



18.49 



11.41 



8.25 



7.36 



10.19 



9.53 



12.22 



11.43 



5.90 



6.00 



FezOs 



+ 



AlaOj 



Per 



Cent 



5.2C 



3.8( 



6.65 



6.97 

 5.77 



Q.ii 



7.55 



5.80 

 3.72 



CeO, 

 Per 



Cent 



4.51 



6.9' 



5.76 



8. IS 

 13. 7t 

 18.1.5 

 19.44 



10. Oi: 



11. 6( 

 15. 2t 



MgO, 

 Per 



Cent 



1.69 



1.47 



1.65 



5.17 

 5.12 



6^21 



6.25 



9.35 

 11.72 



