270 ELEMENTARY ZOOLOGY. 



285. Key to some common Diptera. 



Without wings; external parasites Fleas, sheep-ticks, etc. 



With wings (one pair) . 



Antennae long; many segments. 



Large, slender, with V-shaped suture in back of thorax, 



Tipulidae (crane-flies). 

 Medium size ; no V-shaped suture ; scale-like hairs on margin 



of the wings Culicidae (mosquitoes) . 



Body parallel with surface when at rest, 



Culex (common mosquito). 



Hind end of body raised when at rest Anopheles 



(malarial mosquito). 

 Smaller; appearing in large swarms in air, 



Midges, gnats, punkies. 

 Antenna? short. 



With 5 segments (i. e., 3d" segment of antenna ringed), 



Horse-flies (Tabanidae). 



Large, black Mourning horse-fly (Tabanus) 



Smaller with banded wings . . Banded horse-fly (Chrysops) . 

 With three segments (third segment club-like and bearing 

 a dorsal bristle). 



Resembling bees; eggs laid on mammals; larvae parasitic, 



Bot-flies (CEstridz). 



Not resembling bees Flies (Muscidce). 



Stripes on prothorax; mouth-parts not developed for 



piercing . House fly. 



Similar, but able to bite; annoys stock. . . .Stable fly. 



Large, black; abdomen steel blue Blow-fly. 



Black and white; banded wings; larva bores in sub- 

 stance of apples Apple maggot (fly). 



286. Key to some common Hymenoptera. 

 Females with oviducts suited to boring ; no sting. 



Abdomen with two saw-like structures Tenthredinidce 



(?aw-flies; rose-slugs, currant flies). 

 Abdomen with slender ovipositors; eggs laid in plant tissue, 



where they produce galls Cynipidce (gall-flies) . 



Abdomen slender, with very long ovipositors; lay eggs in 



tissues of other insects Ichn^umonidx (ichneumon flies) . 



Females with sting ; oviducts not suited to boring. 

 Anterior wings not folded lengthwise. 



First segment of abdomen lens-shaped, connecting the rest 

 of the abdomen with thorax Formicidcz (ants) . 



