196 INSECTS INJURIOUS TO VEGETATION. 



visible from above, and the face slopes downwards towards 

 the breast. 



Here may be arranged the singular insects called frog- 

 hoppers (Cercopidid.e), which pass their whole lives on plants, 

 on the stems of wliich their eggs are laid in the autumn. The 

 following summer they are hatched, and the young immedi- 

 ately perforate the bark with their beaks, and begin to imbibe 

 the sap. They take in such quantities of this, that it oozes 

 out of their bodies continually, in the form of little bubbles, 

 which soon completely cover up the insects. They thus re- 

 main entirely buried and concealed in large masses of foam, 

 until they have completed their final transformation, on which 

 account the names of cuckoo-spittle, frog-spittle, and frog- 

 hoppers have been applied to them. We have several species 

 of these frog-hoppers in Massachusetts, and the spittle, with 

 which they are sheltered from the sun and aii', may be seen in 

 great abundance, during the summer, on the stems of our 

 alders and willows. In the perfect state they are not thus 

 protected, but are found on the plants, in the latter part of 

 summer, fully grown and preparing to lay their eggs. In this 

 state they possess the power of leaping in a still more remark- 

 able degree than the tree-hoppers; and, for this purpose, the 

 tips of their hind shanks are surrounded with little spines, and 

 the first two joints of their feet have a similar coronet of spines 

 at their extremities. Their thorax narrows a little behind, and 

 projects somewhat between the bases of the wing-covers,; their 

 bodies are rather short, and their w^ing-covers are almost hori- 

 zontal and quite broad across the middle, which, with the 

 shortness of their legs, gives them a squat appearance.* 



The leaf-hoppers (Tettigoniad.e) leap almost as well as 

 the spittle-insects just mentioned ; but their hind legs are 

 longer, are not surrounded with coronets of short spines, but 

 are three sided, and generally fringed on two of their edges 



* The following species are found in Massachusetts, namely : Cercopis igiii- 

 pecta of my Catalogue, and the parallela, quadrangularis, and obtusa, of Say. 

 The last three belong to Germar's genus Apfirophora, which means spume- 

 bearer. Cercopis, which may be translated impostor, was applied by the Greeks 

 to a small Cicada. 



