312 THE BIOLOGY OF INSECTS 



Cercopods are absent. Immature Thrips resemble generally 

 their parents, but there is a passive stage before the final 

 moult. 



Order lo. MALLOPHAGA 



The Biting Lice are wingless, parasitic insects with short 

 feelers, reduced eyes, biting mandibles, and maxillary palps. 

 There are no cercopods. They live on birds and mammals. 



Order II. ANOPLURA 



The Sucking Lice are wingless parasites with short 

 feelers and a highly modified tubular, suctorial mouth. 

 They live on mammals and the feet, each with a single 

 strong claw, are formed for clinging to the hosts' hair. 

 Cercopods are absent. 



Orderi2. HEMIPTERA 



These are insects with jaws formed for piercing and 

 sucking, the needle-like mandibles and maxillae working 

 to and fro in a dorsal groove extending along the elongate 

 beak-like labium (Fig. 8). There are no cercopods, but 

 the female has often a well- developed ovipositor. 



Sub-order i. HETEROPTERA 



The Bugs have the beak arising towards the front 

 of the head, and the forewings (except for a mem- 

 branous apex) firm in texture. The young insects 

 closely resemble their parents (Fig. 4). 



Sub-order ii. HOMOPTERA 



The Cicads (Fig. 44), Froghoppers, Aphids (Fig. 42), 

 Suckers (Fig. 43), Scales, and allies have the beak 

 arising far back towards the forelegs. The forewings 

 and hindwings are usually alike in texture. The young 

 often diflfer from their parents, and pass through a 



