THE WATER-FLEA. 
216 
about the month of April, if the weather be tolerably 
mild, we see gamboling upon the surface of the shel- 
tered pool ; and every schoolboy, who has angled for a 
minnow in the brook, is well acquainted with this merry 
swimmer in his shining black jacket. Retiring in the 
autumn, and reposing all the winter in the mud at the 
bottom of the pond, it awakens in the spring, rises to 
the surface, and commences its summer sports. They 
associate in small parties of ten or a dozen, near the 
bank, where some little projection forms a bay, or ren- 
ders the water particularly tranquil ; and here they will 
circle round each other without contention, each in his 
sphere, and with no apparent object, from morning until 
night, with great sprightliness and animation ; and so 
lightly do they move on the fluid, as to form only some 
faint and transient circles on its surface. Very fond of 
society, we seldom see them alone, or, if parted by ac- 
cident, they soon rejoin their busy companions. One 
pool commonly affords space for the amusement of 
several parties ; yet they do not unite, or contend, but 
perform their cheerful circlings in separate family as- 
sociations. If we interfere with their merriment they 
seem greatly alarmed, disperse, or dive to the bottom, 
where their fears shortly subside, as we soon again see 
our little merry friends gamboling as before. 
This lively little animal, arising from its winter re- 
treat shortly after the frog, at times in March, continues 
its gambols all the summer long, remaining visible 
generally until the middle of October, thus enjoying a 
full seven months of being ; a long period of existence 
for insects, which are creatures subject to so many con- 
tingencies, that their lives appear to be commonly but 
nef, and the race continued by successive productions. 
A these water creatures must be endowed with much 
perception. Cold as this element is in early spring, 
when the ice of winter is hardly dissolved, and the fluid 
only 6 or 7 degrees above freezing, yet they become 
immediately sensible of this temperature, and are ex- 
cited to animation and the vocations of their being. I 
have never observed the larvae of this creature in any 
state. When they retire in the autumn, these insects 
