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MISC. PUBLICATION 318, U. S. DEPT. OF AGRICULTURE 



Figure 28. — Tree cricket. 



leaves of trees. It has four rather large wings folded over its back. 

 This insect, like the grasshopper, can crawl, jump, or fly. The katy- 

 did is seldom of economic importance. 



Tree crickets. — In the order Orthoptera are a number of small, 

 pale-green insects, about three-fourths of an inch long, known as tree 

 crickets (Oecanthus spp). They have chewing 

 v mouth parts and feed on a wide range of materials, 



including the leaves, blossoms, and sometimes the 

 ripening fruit of plants, or on weakened members 

 of their own kind. Like most other Orthoptera, 

 tree crickets have four wings. The eggs of tree 

 crickets are deposited in the twigs or canes of 

 plants, where they remain over winter, and the egg 

 punctures made in the stems cause this insect to be 

 considered a pest of raspberry and similar small 

 fruits. Stomach poisons will kill the nymphs, and 

 burning the canes containing the eggs will destroy 

 them. 



Mantids. — Not all Orthoptera are injurious. 

 The mantids are beneficial because they feed on 

 other insects, many of which are pests. Mantids 

 can be easily distinguished from other Orthoptera 

 by the much elongated thorax or waist part of the 

 body, and by the large front legs, which are fitted 

 for grasping their prey. The four wings usually 

 are folded back over the hind part of the body. 

 The total length of the body of the species here 

 illustrated is approximately 2V 2 inches. These in- 

 sects have incomplete life changes. The eggs are 

 laid in clusters, usually covered with dried froth, 

 on branches and twigs of trees or shrubs and re- 

 main there through the winter. The next spring 

 the eggs hatch, and the young mantids start their 

 beneficial work of destroying other insects. Since 

 the mantids are friends of man, we need not worry 

 about control measures. The one shown here is 

 Stagmomantis Carolina. 



Roaches. — The cockroaches make up 

 another family of the Orthoptera. Two 

 kinds are rather common over the United 

 States, the small German roach and the 

 larger American roach. These insects 

 prefer to remain in dark places, although 

 at times they do venture into the light. 

 Their very flat bodies permit them to get 

 into extremely narrow cracks. These in- 

 sects have four wings, but they are seldom 

 f used. They feed primarily on human 



foods and waste food products. Cock- 

 roaches have incomplete life changes. 

 After the eggs hatch, the nymphs shed 

 their skins several times and finally reach 

 J the adult stage. Some roaches live in the 

 figure 30.— Roach. woods in the loose bark of trees or logs, 



Figure 29. — Mantid. 



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