404 



AN INTRODUCTION TO ENTOMOLOGY 



on each hemelytron yellow. Another common species is Clasioptera 

 ohtusa. This occurs on black alder in summer and autumn. It is of a 

 claret-brown color above, marked with two pale bands on the vertex, 

 two on the prothorax, and a wavy, broader band on the hemelytra. 

 The membrane is often whitish, the waved band is extended exteriorly, 

 and there is a pale V-shaped figure on the end of the scutellimi. 



Family MEMBRACID^ 



Fig. 469. — A, Spongophorus ballista; B, Spongophorus 

 querini. 



The Tree-Hoppers 



The most useful character for distinguishing members of this 

 family is the prolongation of the prothorax backward above the 



abdomen; some- 

 times it extends 

 back to the tip of 

 the abdomen and 

 completely cov- 

 ers the wings. 

 This develop- 

 ment of the 

 prothorax re- 

 sembles that 

 which occurs in 

 the pigmy lo- 

 custs, the sub- 

 family Acrydiinse 

 of the order Or- 



thoptera. In many of the Membracidse, however, the prothorax is 

 not only prolonged backward but is extended sidewise or upwards, 

 with the result that in some cases the insect presents a most bizarre 

 appearance ; this is especially true of certain tropical forms ; Figure 469 

 represents two species found in Central America. 



Many species of the Membracidce live upon bushes or small 

 trees; others inhabit grass and other herbaceous plants. Although 

 these insects subsist upon the juices of plants, they rare- 

 ly occur in sufficient nimibers to be of economic impor- 

 tance. Sometimes the females injure young trees by lay- 

 ing their eggs in the bark of the smaller branches and in 

 buds and stems. Many members of this family excrete 

 honey-dew and are attended by ants, especially in the 

 nymphal stages, as are the aphids. The adults are good Fig.470. — Cer- 

 leapers ; hence the common name tree-hoppers. esa bubalus. 



This family is well represented in this country; 

 one hundred eighty-five species, representing forty-three genera, are 

 now listed. Among our more common species are the following. 



The Buffalo tree-hopper, Ceresa bubalus. — The popular name of 

 this species refers to the lateral prolongations of the prothorax, 

 which suggest the horns of a buffalo (Fig. 470). The life-history of 



