INSECTA, A CLASS OF ARTHROPODS 



193 



Classification. We cannot study all, or even one, species 

 thoroughly. However the accompanying table will show the 

 names and representatives of a few of the sixteen different orders, 

 and then we shall take up two or three types in greater detail. 



Order 



Orthoptera 

 Pseudo-neuroptera 

 Hemiptera 

 Diptera 

 Coleoptera 

 Lepidoptera 

 Hymenoptera 



antennae 

 /' \ 



Representative 



grasshopper cricket locust 

 dragon-flies 



true bugs lice scale insects 

 flies mosquitoes fleas, gnats 

 beetles 



moths butterflies 

 bees ants wasps 



auditory organ 

 ocellus : 



' head compound eye I 



ovipositor 



femur* 

 tibia-'' 



torsal segments 



FIG. 61. Locust (enlarged) with external parts named. From Kellogg. 



The Grasshopper. The grasshopper (which really is a locust) 

 will be taken as a type of all the insects. It belongs to the order 

 Orthoptera, which means " straight winged " and refers to the 

 narrow folded wings, held straight along the body. 



Exoskeleton. As in all Arthropods, the skeleton is external, 

 but differs from the crayfish in that it contains no lime. It consists 



