284 



PRAIRIE COMMUNITIES 



sometimes taken. The slender meadow grasshopper (Xiphidium fasci- 

 taum) is common, but breeds in the sedge zone. A flea-beetle (Monachus 

 saponatus), the i2-spotted Diabrotica (Diabrotica i2-punctata) (156), 

 and the salt-meadow snout-beetle (Endalus limatulus) (156) are the 

 chief beetles. 



The spiders (Epeira trivittata and Tetragnatha laboriosa) are common. 

 The flies of this girdle are perhaps the most noteworthy insects Several 

 species of brownish or yellowish flies with conspicuously marked wings 

 are nearly always common. They are Sciomyzidae (Tetanocera plumosa 

 and umbrarum) (Fig. 283). Other characteristic 

 flies are Osinidae (Chlorops sulphured Leow.), 

 midges, mosquitoes, Dolichopodidae, Rosophilidae, 

 and Anthomyidae. The blue and yellow moth 

 (Scepsis fuhicollis) is common. 



Boneset and sedge girdle: The buffalo tree- 

 hopper (Ceresa bubalus) (Fig. 259) is found here. 

 The dusky (Fig. 261) and tarnished plant-bugs 

 (Fig. 262) suck the juices of the mint and other 

 plants. The ambush-bug and the damsel-bug 

 often lie in wait in the blossoms for prey. 



290 



"' 



FIG. 290. Larva of the salt-marsh caterpillar (Estigmena acraea Dru.) ; natural 

 size (after Forbes). 



FlG. 291. Adult female of the same; natural size (after Forbes). 



Aphids occur and with them are the syrphus flies, lady-beetles, 

 and other aphid enemies (164), which are discussed more fully in 

 connection with high prairies. The bright green beetle (Chryschus 

 auraius) feeds on the small-leafed milkweed. One of the corn "bill- 

 bugs" (174) or snout-beetles (Sphenophorus pertinax Oliv.), another 

 snout-beetle (Cryptocephalus venustus), common garden pests, as well as 

 the leaf -beetle (Typophorus canellus) are common (174). 



One of the most characteristic groups of the low prairie is that of the 

 grass-feeding larvae. The first of these to appear in spring is the grass 



