Abstract 



Insects of the family Hydroptilidae (Trichoptera) are dealt 

 with in the following manner. Brief discussions of the family and 

 genera; tables for determining the 15 genera; a key for deter- 

 mining each species (males), including 180 species in all; an 

 increase of 102 species since Ross (1944) . This encheiridion also 

 includes a check list of the species as to provinces (Canada) and 

 states (U.S.A.) to date; the original reference for each species; 

 illustrations of the male genitalia of each species described up 

 to and including August 1977; selected literature references. 



KEY WORDS: Trichoptera, Hydroptilidae, North America. 



