46 Key to Families of North American Insects. 



9. Wings acute at apex; outer margin of fore wings distinctly emarginate, cross- 

 veins with bristles; hind wings with a fork to the cubitus that extends very 



close to the hind margin. (Lomamyia) BEROTHID^E 



Outer margin of fore wing not emarginate, crossveins not bristly. (Sisyra, 

 Climacia) SISYRDXE 



ORDER PANORPATJE. 

 (MECOPTERA.) 



Small to moderate-sized predatory insects with the head drawn 

 out to form a sort of beak; wings when present long, narrow and 

 similar, crossveins and veins moderately numerous; mandibles 

 small, antennae long and hair-like; prothorax small; legs long, 

 similar, fitted for running; coxa? large, pendant and approximate* 

 tarsi five-jointed; abdomen usually slender, cerci small, ninth 

 segment of male greatly swollen and reflexed. Metamorphosis 

 complete, larvae resembling caterpillars. Scorpion flies. 



1. Three ocelli present; winged species, costal margin without crossveins 2. 



Ocelli absent 3 



2. Tarsi with two claws; cubitus of fore wings forked near the base. Scorpion- 



flies. (Pan6rpa) (PI. 9, figs. 190, 191, 192, 194) PANORPUXE 



Tarsi with a single claw; cubitus simple. (Bittacus) (PI. 9, fig. 193). 



BITTACUSIIXE 



3. Wings well developed, costal cell with many crossveins. (Merdpe.) 



MEROPIILE 

 Wingless, or with very short wings. (BorSus) BOREIDjE 



ORDER TRICHOPTERA. 



(PHRYGANOIDEA.) 



Small to medium-sized, slender, flying insects; head movable^ 

 vertical, eyes prominent, ocelli three or none, mandibles vestigial, 

 palpi prominent, antennae thread-like, often very long; prothorax 

 small; wings more or less clothed with hairs, with many veins and 

 a few crossveins, the hind wings with a folded anal area; legs 

 similar, coxae pendant and approximate, tarsi five-jointed. Meta- 

 morphosis complete, larvae aquatic case-bearers. Caddice flies. 



1. Minute, often pretty, moth-like pubescent species, whose anterior wings are 

 closely covered with projecting, clubbed hairs; marginal fringe of wings 

 very long, that of hind wings longer; discal cell of hind wings open or want- 

 ing; wings usually very long and narrow, more or less pointed; antennae at 

 most as long as the fore wings, usually much shorter and usually thickened i 



