270 



THICKET COMMUNITIES 



milkweed beetle (Tetraopes tetraophthalmus Forst.) (40, p. 136), and the 

 leaf-beetle (Doryphora divicollis) ; the latter is very characteristic. The 

 milkweed flowers attract hosts of flies which are preyed upon by vari- 

 ous digger-wasps; bees are numerous, gathering honey. The ground- 



268 269 



FIG. 268. The four-lined leaf-bug (Poecilocapsus lineatus); a, adult; b, c, imma- 

 ture forms; 5! times natural size (from Lugger). 



FIG. 269. A long-legged fly (Psilopodinns sipho Say) ; enlarged (from Williston 

 after Lugger) . 



270 271 



FIG. 270. A large robber-fly (Dasyllis sp.); natural size (from Williston after 

 Kellogg). 



FIG. 271. A syrphus fly (Eristalis lenax); 15 times natural size (from Williston 

 after Kellogg). 



cherry is the food plant of the "Spanish fly" (Epicuata) and the 

 Colorado potato-beetle. On the thistle we find the larvae of the cos- 

 mopolitan and painted-lady butterflies (Pyrameis huntera Fab. and 

 cardui Lin.). One of the most characteristic bugs is the 4-lined 



