0.20 - 



0.10 



0.00 



May 



CA 



CB Bl 



0.40 - 



0.30 



0.20 



0.10 



0.00 



Nov. -Dec, 



1974-75 



1979-80 



D 



CA 



CB 



Bl 



Figure 7, 



Graphic comparisons of organic carbon percentages for May and November - 

 December between the 1974-75 and 1979-80 collections. 



31 



