HOW TO KNOW THE IMMATURE INSECTS 



4a. Thorax with tubercles or spines. 



Fig. 377 Family MEMBRACIDAE 



About 200 known species of treehoppers are repre- 

 sented in North America. They are plant feeders. 

 Eggs are laid in groups arranged in two parallel 

 slits in twigs of trees or shrubs. The nymphs ara dif- 

 ferent from their adults in the absence of the pronotal 

 CI process, but filaments or spinose projections are often 

 developed on the tergites. 



Fig. 377. Stie^ 

 tocephala sp. : 



a, 4th instar; 



b, 5th instor. 



4b. Thorax without tubercles or spines 5 



5a. Hind tibiae with 1 or 2 stout teeth, and crowned with short, stout 

 spines at the tip. Fig. 378 Family CERCOPIDAE 



They are called froghoppers on 

 account of the frog-like appearance 

 of both the young and the adults. 

 They are also known as spittle-bugs 

 since the niunphs of some genera hide 

 in a mass of white froth. The froth- 

 ing is the result of a fluid issu- 



Fig. 378. a, 

 marius (L.) ( 

 last instars), 



("ist'intel^mVcro" ^d ^"5 &om the onus becoming blown 



.he lined spi«,tb'i,!%*lf..:.T..n': '"♦° ^"^^^^^ ^ ^^ °°'"- 

 eatus (L) 



5b. Hind tibiae with a row of spines. 



Fig. 379 Family CICADELLIDAE 



Fig. 379. 

 hopper, 

 (Harris) 

 stars. 



The potato leaf- 

 Empoasca foboe 



2nd and 4th in- 



There are more than 700 species of 

 leafhoppers known in the United States. 

 They are able to leap powerfully and 

 feed on many different kinds of plants. 

 The leafhoppers not only cause dam- 

 age to cultivated plants but also trans- 

 fer plant diseases. 



137 



