397 
- 
Borrom Fauna, CHANNEL, 1 MILE ApovE LivERPooL To HAvANa, 1915 
Small 
Viviparidae Insects, 
aed Solis we worms, Total 
Pleuroceridae | sphaeriidae Crustacea 
Number per sq. yard, 
Average 1,294.0 3.0 171.8 1,468.8 
5 8 coll.’s 
Pounds per acre, = 
Average 5,156.0 0.1 24.7 5,180.8 
8 coll.’s 
Per cent. of total, 
(By weight) 99.5% 0.4% 
Average bottom-fauna poundages in the 4~7-foot zone above Mile 
129 in 1915 (1,436.2 Ibs. per acre) were nearly twice those in the chan- 
nel opposite (878.3 Ibs.). Below Mile 129, where they were 2,122.0 lbs. 
they were less than half the average channel valuation (5,180.8 lbs.).° 
No collections were taken above Mile 129 within the 4-foot line, but be- 
tween Liverpool and Havana six collections in the 1-3-foot zone showed 
an average valuation of 917.7 lbs. per acre. In the 4-7-foot zone, both 
above and below Liverpool, Sphaeriidae were relatively much more 
abundant than either in the channel or the 1-3-foot zone, making 40 
to 80% of the average weight of collections. In the 1-3-foot zone below 
Mile 129 the weight-composition of the bottom fauna was on the whole 
nearly identical with that of the channel (Viviparidae and Pleuroceridae 
96% ; Sphaeriidae and smaller Gastropoda 2.3% ; insects, etc., 1.1%). 
Borrom Fauna, 4—7—-root ZONE, CopreERAS CREEK DAM TO 1 MILE ABOVE 
LiverPooL, 1915 
cee , Small 
Viviparidae Insects, 
and 2s oda | worms, Total 
Pleuroceridae Sphaeriidae Crustacea 
Number per sq. yard, 
Average 302.2 1,212.5 96.0 1,610.4 
4 coll.’s 
Pounds per acre, 
Average 814.3 606.2 15.7 1,436.2 
4 coll.’s 
Per cent. of total, 
(By weight) 56.6% 42.2% 1.0% 
