PHYLUM ARTHROPODA — CLASS INSECTA 



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in many of the states of western America. Mills reports that the 

 Collembola are of some economic importance, damaging, in the main, 

 tender plant tissue. 



Subclass Pterygota. — Paurometabola are insects with gradual 

 metamorphosis. The following are some of the more important 

 paurometabolous orders. 



Fig ISO. — American German (ventral view), and Oriental Cockroaches (left to 

 riglit). (From Knowlton, permission of Utah Agricultural Experiment Station.) 



Fig. 181.— Praying mantis, Stagmomantis sp. It is named for its pose. 



Order Orthoptera. — This order contains the grasshoppers, katy- 

 dids, crickets, cockroaches, mantids, and walking sticks. Members of 

 this order usually po-ssess two pairs of wings ; some species, however, 

 have their wings greatly modified or reduced, and some do not 

 possess wings at all. The mouth parts are of the biting type. The 

 legs are highly developed for use in getting and holding food and 



