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3. GENERAL AVERAGE VALUATION 
A simple average (without weighting to compensate for irregularity 
in distribution of collections within different lake classes) of the total 
of 266 bottom collections of 1914—1915 from the five classes of lakes 
and backwaters (including dead timber and brush areas) figures out 
at 402 lbs. per acre. Since the general average of 848 lbs. per acre for 
the Class II lakes (Quiver, etc.) applied to but 620 acres at the low 
water of 1901, while the average of 352 lbs. per acre for the Class I 
lakes covered 3,390 acres at the same gage, it is evident that a simple 
average of this sort is unfair and likely to be unduly high. As we have 
not complete acreage figures for different depths at recent gages pre- 
vailing in midsummer, and lack, in particular, exact figures on the dead 
timber acreage, a close general average of all the lakes and backwaters 
studied in the two years, based on accurate acreage weightings, can not 
now be figured. If we assume, however, that on the average the ex- 
pansion in lake acreage between 4.2 and 8 feet, Havana, is about the 
same in all of the first four classes of lakes except Class II, we shall 
not go far wrong in weighting the class average of I to IV, excluding 
the dead timber and brush areas, with the low-water acreage for 1901. 
The general bottom-fauna average for Classes I—IV, inclusive, figures 
out in this way at 285 lbs. per acre. If, again, we assume that the usual 
ratio of adjacent dead-timber acreage to the total acreage of lakes and 
backwaters at gage 8 feet, Havana, is about the same as in Thompson 
Lake (around 30%, estimated), and weight the Class I—IV average 
(285 Ibs.) and the Class V average (187 lIbs., dead timber and brush 
areas) with “per cent.” acreage figures on this basis, we obtain a gen- 
eral average of bottom fauna for the two years, for all classes of lakes 
and backwaters, all depths, of 255 lbs. per acre, or almost exactly the 
general river average for 180.5 miles below Chillicothe (261 Ibs.), but 
only about one third of the all-zone river average for the 59.3 miles be- 
tween Copperas Creek and Lagrange dams (705 lbs.). 
