XI 



PHYLUM ARTHROPODA 



587 



an elongated sucking tube, Avhich is rolled up spirally ; the other 

 parts of the mouth are rudimentary, with the exception of the 

 labial palpi. The prothorax is fused with the mesothorax. The 

 metamorphosis is complete. 



This order includes Butterflies (Fig. 475) and Moths. 



ORDER 7. COLEOPTERA. 



Insects in which the anterior pair of wings take the form of 

 hard horny wing-cases, or elytra, which, when at rest, are folded 

 up along the back and cover over the 

 folded-up membranous posterior wings. 

 The prothorax is movable on the other 

 segments. The jaws are fully developed, 

 and adapted for biting and chewing. The 

 metamorphosis is complete. 



This order includes the true Beetles 

 (Fig. 470). 



ORDER 8. HYMENOPTERA. 



Insects in which both pairs of wings 

 are present and membranous. The mouth 

 parts are adapted both for biting and 

 licking. The prothorax is united with 

 the other segments of the thorax. There 

 is a complete metamorphosis. 



Included in this order are Bees (Fig. 

 493) and Wasps, Ants (Fig. 494), Gall-flies, 

 Ichneumons. 



FIG. 476. Beetle (Crioceris) 



with larva. (After Guerin 

 and Percherou. 



Systematic Position of the Example. 



The Cockroach is a member of the order Ortlioptera and of the 

 sub-order Orthoptera gcnuina. which comprises all the members of 

 the order with the exception of the aberrant group of the Ear- wigs 

 (sub-order Dcrmcptcra). Of the Ortlioptera gcnuina there are 

 three divisions,, the Cursoria, to which the Cockroaches belong ; 

 the G-rcssoria, comprising the Mantidce and Phasmidw, or Stick- and 

 Leaf-insects and their allies ; and the Saltatoria, including the 

 Grasshoppers, Locusts, and Crickets. The division Cursoria com- 

 prises the single family of the Cockroaches (Blattidce), characterised 

 by the deflexed head, the flat oval body, the large prothoracic 

 tergum, the long antennae, the three pairs of legs similar, with 

 large coxae entirely covering the sternal surface of the thorax, the 

 five-jointed tarsi, and the presence of anal cerci. Periplaneta 

 belongs to a section of the family distinguished from the rest by 

 the femora being spiny underneath, and by the valvular character 

 of the last sternum in the female. 



