APPENDIX 



193 



Table 21. The variations in the percentages and in the amounts of 

 the pentosans found in the nannoplankton material. Compare with 

 the net plankton in table 12. 



Year 



Number 



of 

 Analyses 



Pentosans, Per Cent 

 Ash Free 



Pentosans, Milligrams per 

 Cubic Meter of Water 





Maximum 



Minimum 



Mean 



Maximum 



Minimum 



Mean 



1915 

 1916 

 1917 



32 



8 



2 



7.39 

 7.61 

 3.71 



2.84 

 3.64 

 3.52 



4.87 

 5.28 

 3.64 



115.6 

 144.0 



96.6 



42.7 

 53.7 

 47.4 



78.9 

 86.6 

 72.0 



Table 22. The range of the variations in the percentage and in the 

 amount of crude fiber in the nannoplankton of Lake Mendota. Com- 

 pare with the results for net plankton, table 13. 



Year 



1915 

 1916 

 1917 



Number 



of 

 Analyses 



34 



17 



4 



Crude Fiber, Per Cent 

 Ash Free 



Maximum Minimum Mean 



5.36 



9.27 



11.17 



1.27 



4.20 

 3.86 



3.02 

 6.46 

 6.73 



Crude^Fiber, Milligrams 

 per Cubic Meter of Water 



Maximum Minimum Mean 



85.8 

 215.7 

 158.2 



24.7 

 57.2 



78.8 



49.0 

 106.0 

 109.2 



