314 Insects and their Surroundings 



seen also on many Aphids. In the latter insects, how- 

 ever, the waxy dress retains its thread-like form as for 

 instance in the "woolly aphid" or "American blight" 

 of orchards. The young nymphs of a nearly allied 



Fig. 170. — Scale-insect {MytilasJ>is poiiwrum, Bouch6). a. female, from 

 beneath, showing eggs protected by "scale" ; b. from above, magnified 

 24 times ; c. female scales on branch, natural size ; d. male scale, magni- 

 fied 12 times ; e. male scales on twigs, natural size. From Howard, 

 Yearbook, U.S. Dept. Agr., 1894. 



family of Homoptera — the Froghoppers — protect 

 themselves by a frothy liquid — the well-known 

 "cuckoo-spit" which entirely surrounds them as 

 they lie sucking their food at the base of a leaf-stalk. 



