12 Descriptive Zoology. 



ORDER ORTHOPTERA. 



The Orthoptera. We have selected the grasshopper as 

 'the best available type of the class Insecta and also of the 



order Orthoptera. The word 

 Orthoptera means straight - 

 winged, probably in allusion to 

 the mode of folding the hind 

 wings. The first pair are thick- 

 ened, serving as a cover for the 

 second pair, which are folded 

 when at rest. The mouth parts 

 are fitted for biting. The de- 

 velopment is direct. 



Protective Resemblance. 



The green grasshoppers, es- 

 pecially the katydid, are note- 

 worthy for their resemblance to 

 leaves, both in color and form. 

 The walking stick (Fig. 7) so 

 closely resembles a twig that 

 it is seldom discovered by 

 casual observers. These in- 

 sects afford fine examples of 

 the advantages of protective 

 resemblance. 



The green grasshoppers have 

 a windowlike membrane on the 

 FIG. 7. A WALKING STICK INSECT tibia of each fore leg that is 



(Diapheromerafemorafa) ON TWIG. supposed to be an organ o f 

 From Jordan and Kellogg' s Animal Life. , 



hearing. 



Classification of Orthoptera. The families are : the short- 

 horned grasshoppers (locusts), which we have studied ; 



