Bugs, Cicadas, Aphids, and Scale-insects 191 



much like scale-insects and have the same general habits. Provided with 

 a delicate long sucking-beak, each individual remains fixed in one spot on 

 a green leaf, sucking up its food, the plant-sap, as it needs it. The adults 

 which finally issue from the beautiful little cases have four rounded wings, 

 pure white or with small dusky spots and golden yellow, finely beaded 

 margins; each wing has but a single vein, and is dusted with a granular 



FIG. 260. The California live-oak scale, Cerococcus ehrhorni. (Photograph by Rose 



Patterson; natural size.) 



white waxen powder or "bloom." The tiny white or pale-yellow eggs 

 are laid on leaves in a circle or the arc of one, in one or more rows, and 

 vary in number from three to thirty; each egg has a minute but noticeable 

 curving stem. The young hatch in from ten to thirteen days, and move 

 freely about, but never seem to get more than about one inch from the 

 deserted shells. This activity lasts for from ten to forty hours; then 

 the young attach themselves to the leaf by inserting the sucking proboscis, 



