87 
2. Note, however, the presence of the con¬ 
spicuous white feathery gills which form tufts at the 
side of the head. 
3. Note that the nymph and larvae do not rise 
to the surface to breathe as do those of mosquitoes. 
Fig. 33. Nymfhs of Chironomus and Corethra 
4. Note the curious rhythmic bending movement 
of the larvae and nymph of Chironomus which, when 
they are present in numbers, gives the mud at the 
bottom of the pool a curious appearance. 
LITERATURE 
Miall. Aquatic Insects 
