146 
HALE HOURS WITH INSECTS. [Packard. 
Of those insects which extract air from the water in which 
they live and are not obliged to ascend to the surface, is the 
young of the plumed gnat (Fig. 110, Chironomus oceanicus , 
male* and beneath, head of female; a, larva and head en¬ 
larged). These worms are very abundant in every mud 
puddle, but the species .here figured lives at all depths in 
fig. no. 
Ocean Gnat; a, larva, and head enlarged. 
the sea down to over a hundred feet. Some larvae of an¬ 
other species were dredged in Lake Superior by Mr. S. I. 
Smith at a depth of one hundred and fifty-five feet. They are 
usually provided with two pairs of fleshy filaments, perme¬ 
ated by one or two slender tracheal twigs, connecting with 
a slender pair of tracheae running through the body, and 
