ARTHROPODA 



i8i 



men consisting of eleven segments. The head is rather elongated 

 dorsiventrally and bears two rather large laterally situated com- 

 pound eyes with many facets. There are three simple eyes, the 

 ocelli, one near the middle of the forehead and the others situated 

 near the bases of the antennae. The antennae are long and seg- 

 mented to give flexibility. They bear many spines which furnish 

 increased points of contact. The mouth parts consist of a dorsally 

 situated labrum; two crushing mandibles with serrated edges; a 

 pair of maxillae, each provided with a maxillary palp; and a ventral 

 labium with a pair of labial palps. 



antennae 



•ovipositor 



fern uri 

 tibia'' 



tarsal segments 



Fig. 83. Locust, with external parts named. (From Kellogg, The Animals and Man. 



Courtesy of Henry Holt & Co.) 



The thorax consists of three segments, prothorax, mesothorax and 

 metathorax, with a pair of legs attached to each of the segments. 

 The third and second thoracic segments bear wings in the grass- 

 hoppers. The anterior pair of wings are wing covers and used for 

 gliding, while the posterior pair, folded like a fan when at rest, are 

 the true flying wings. 



The abdomen consists of eleven segments. In the male there are 

 nine distinct movable sterna. The posterior end in the female is 

 modified by hardened ovipositors, the tips of which are protruded 

 beyond the eleventh tergum. During oviposition, the tips are 



