22 
bare or covered with trees according to its height above the 
usual water level. 
Thompson’s Lake lies wholly within the bottom-lands of the 
main river, and its banks are consequently everywhere low and 
flat. It is five miles in length by about half a mile in width at 
an average midsummer stage. When the water is moderately 
high it can be entered by skiffs from either end, but as the river 
falls the lake is shut off below, and connects with the stream 
only by a somewhat tortuous narrow chanel about two miles in 
length at its northern end. Neither this nor Quiver Lake ever 
goes dry, the water in the deepest places being not less than 
three and a half or four feet during the dryest seasons. Phelps 
Lake, on the other hand, is a pond about half a mile long by a 
fourth as wide, having neither inlet nor outlet after the overflow 
has receded, rarely drying up entirely, but not infrequently 
being reduced to a few shallow pools. It is completely sur- 
rounded by a bottom-land forest, and its bed is a mere shallow 
depression in the mud. 
_ Beside our regular station work, occasional collections were 
made from various other waters, including Spoon River, Matanzas 
Lake,— three and a half miles below Havana, on the eastern side 
of the river,—Clear Lake, Dogfish Lake, Mud Lake, Liverpool 
Lake, and Quiver Creek. 
At each of the above regular stations thoroughgoing collec- 
tions and careful observations were made at intervals of from 
one to three weeks, the time varying according to the nature 
of the station and the teachings of our experience. The mid- 
stream and mid-lake collections were of two kinds, qualita- 
tive and quantitative; the former made at surface and bottom 
with towing net and dredge, and the latter with a plankton net 
of the finest bolting cloth (Number 20) hauled from top to bot- 
tom at a regular and uniform rate and over identical distances. 
As the waters in which we worked were much too shallow for 
profitable vertical hauls—often not more than five or six feet in 
depth—we tightly stretched a line one hundred feet long ob- 
liquely from bottom to surface, and drew the quantitative net 
along this line, to which it was suspended in a horizontal posi- 
tion by a carriage running along the line on wheels. The con- 
tents of the dredge were assorted by the aid of a set of bag sieves 
of netting and of finer cloth, fitted closely together as one 
