THE TRUE BUGS 



125 



(Cercopidae) are called " frog-hoppers " or " spittle-insects." Within 

 this frothy mass the little nymph molts and grows and finally 

 forms a little clear space about its body, around which the foam dries, 

 forming a little chamber within which it transforms to the adult. 

 Though very commonly in evidence, few of this family are injurious. 

 The leaf -hoppers (Jassidae) are among the most abundant of the 

 Homoptera. Take a net and sweep back and forth in any meadow 

 and you will secure hundreds of 

 them, Professor Herbert Osborn 

 having estimated that frequently 

 over a million live on an acre of 

 grassland. They are more slender 

 than the two preceding families, 

 from an eighth to a fourth of an 

 inch long, and of a brownish, 

 green, or red color, the green and 

 red often being arranged in stripes, 

 giving a very striking coloration. 

 The grape leaf-hopper (Typhlo- 

 cyba comes), commonly called the 

 grape thrips (although it is not a 

 true thrips), is one. of the most 

 serious enemies of the vine. In 

 late summer the foliage will often 

 be brown as a result of th.eir work, 

 and a slight jar will cause them 

 to fly off in clouds. They are 

 small yellowish hoppers, scarcely 

 an eighth of an inch long and 

 strikingly marked with red and black. A yellowish-green species, 

 the rose leaf-hopper (Empoasca rosae), often does considerable 

 injury to rose foliage, and a similar one, the apple leaf-hopper 

 (Empoasca mali), is found on the apple and frequently becomes a 

 serious pest in the nursery. The presence of these leaf-hoppers 

 is always indicated by the numerous white cast skins of the nymphs 

 clinging to the undersides of the leaves. So'me species fly to lights 

 in large numbers. They hibernate as adults, and the eggs are 

 usually laid just beneath the surface of the leaf of the food plant, 



FlG. 171. Aphrophora 4-notata Say, 

 a common frog-hopper . 



(After Lugger) 



