432 THE INSECT WOELD. 



The Hydropsyches (Fig. 420) and Rhyacophili (Fig. 421) are 



Fig. 420. Hydropsyche (Phryganea) atomaria, larva, pupa, imago, and larva-ease. 



small insects which resemble the Phryganece very closely. Their 



I 



Fig. 421. Ehyacophilus vulgatus, arva, pupa, cocoon, and imago (male). 



larvae have, for the purposes of respiration, some gills, others re- 



