67 
Not only in Thompson, Dogfish, and Liverpool lakes in 1920, but in 
Quiver Lake also in its muddy part, we found nothing at all surviving 
out of a list of some ten or twelve families of minor insects and miscel- 
laneous small bottom-animals other than the groups already passed in re- 
view that were common in all of these lakes in 1914—1915. Though this 
item of loss in the lakes near Havana has been greater since 1915 than 
in the river just above Havana, the decrease in poundage therein in com- 
parison to totals of all small bottom-animals has not been very large, the 
figures that follow showing that at the best the total weight of “other in- 
sects, etc.,” in the bottom muds of these lakes in 1914—1915, did not run 
to twenty pounds per acre. In the Quiver Lake “channel” and in the 
sand and mud toward the beach side our collections showed leeches, 
Bryozoa, larvae of caddis-flies, and nymphs of Odonata in good variety 
and number, the “channel” average in 1920 (82 pounds per acre) being 
larger than in 1915. 
“OTHER INSECTS,’ WorMS, CRUSTACEA, ETC., OF THE BoTrom Muns. 
LAKES NORTH OF HAVANA, 1914—15 anp 1920 
I. Mud bottom, 2 to 6 feet 
Number per square yard Pounds per acre 
1914+-1915 1920 | 19141915 | 1920 
Liverpool Lake* 16 0 3 | 0 
Thompson Lake* 32 0 5 0 
- 
Dogfish Lake; 22 0 13 0 
Quiver Lake+ 83 0 19 0 
II. Sandy or sand and mud bottom 
Quiver Lake “channel” * 26 36 3 | 32 
Quiver Lake, sandy shore, Not 
east side Not separately counted) 15 separately 8 
| valued 
* Figures in 1914—1915 columns are for year 1915. 
t+ Figures in 1914—1915 columns are for year 1914. 
The decrease in average valuation of all small bottom-animals in the 
four lakes since 1915, with the sandy portions of Quiver Lake omitted, 
has been in ratios quite similar to those of average decline in the period in 
