32 T&E ORDERS OF INSECTS. 



they cause great annoyance. Some species will also settle on 

 man ; and it is quite common to feel a sharp sting on your hand 

 in a wood, and see a pretty green fly, rather larger than a house- 

 fly, with golden eyes and variegated wings, standing on your 

 hand in a pool of blood. 



Among the largest of the Diptera are the Asilidce ; hairy flies, 

 with thick legs, which feed on other insects. Asilus Crabroni- 

 formis is an inch long ; the wings are tinged with yellowish, and 

 the body is black, with the hinder half of the abdomen yellow. 



The Syrphida are pretty flies, often chequered with black 

 and yellow, which may be known at once by their peculiar 

 hovering flight, darting away like an arrow when disturbed, and 

 hovering again at the end of their flight. 



The Muscida are a very large group, the larvce of which 

 generally feed in decaying vegetable or animal matter. .The 

 common house fly and the Blue Bottle may serve as examples. 



The (Estridce, or Bot Flies, are still more injurious to cattle 

 than the Tabanida, as their larvse live under the skin or in the 

 stomach of our domestic animals. They are large, stout flies ; 

 but many of the Hippobostida and Nycteribidcs, which include 

 the Forest Flies, Bird Flies, Sheep-ticks, and Bat-ticks, are 

 apterous ; and their long, hairy, spider-like legs give them a 

 superficial resemblance to some of the eight-legged parasitic 

 Amchnida, which are not true insects, and to which the name 

 Tick more properly belongs. The Fleas (Pulicida) are now 

 considered by most entomologists to be a wingless and aberrant 

 family of Diptera. 



BOOKS ON ENTOMOLOGY. 



The following books may be recommended as treating of Insects 

 in general, without confining themselves to any special Order ; 



Staveley's British Insects. (Coloured Plates). 



Dallas' Elements of Entomology. (Woodcuts). 



Westwood's Introduction to the Modern Classifica- 

 tion of Insects. 2 vols., woodcuts (out of print, and only 

 to be met with occasionally). 



Pashord's Guide to the Study of Insects. (Wood- 

 cuts). Treats chiefly of North American insects. 



Kirby and Spence's Introduction to Entomology. 

 (Treats of habits, etc.). 



Ormerod's Injurious Insects. (WoodcutsX 



