1935 ] 
New Near otic Mecoptera 
111 
out, is of little taxonomic value, because it is subject to 
much individual variation. 
Since there are now more than twice as many species of 
Boreus as were known when my key was published (1931), 
new keys to both sexes are included here. 
Key to Males of Boreus 
1. Hypandrium entire 2. 
Hypandrium emarginate 8. 
2. Wings and all of body black 3. 
Wings brown or yellow 4. 
3. Body covered with long, white pilosity; hypandrium 
slenderly triangular reductus Carp. 
Body covered with very fine, white pubescence, hypan- 
drium broadly triangular unicolor Hine. 
4. Fore wings gradually tapering throughout their entire 
lengths 5. 
Fore wings strongly narrowed in proximal half 6. 
5. Fore wings very broad and long, two and one-half times 
the length of the rostrum (British Columbia) 
elegans n. sp. 
Fore wings not so broad and of moderate length, only 
one and one-half times the length of the beak (east- 
ern United States) nivoriundus Fitch. 
6. Distal half of wings very slender; rostrum twice the 
length of the eye intermedins Lloyd. 
Distal half of wing normally slender ; rostrum only one 
and one-half times the length of the eye 7. 
7. Body except wings black or nearly so 8. 
Body brown or reddish brown ..calif ornicus var. cali- 
fornicus Packard. 
8. Wings yellow-brown borealis Banks. 
Wings dark brown calif ornicus var. fuscus n. var. 
9. Body covered with long white or yellowish pilosity 10. 
Body covered with very fine white pilosity 11. 
10. Wings and body deep black nix n. sp. 
Wings yellow or light brown, body dark brown 
pilosus n. sp. 
11. Wings yellowish-brown, much lighter than the dark 
brown body isolatus n. sp. 
