INSECTS INJURIOUS TO CURRANT AND GOOSEBERRY 489 



the twigs of the infested plants and hatch as the bushes come 

 into full leaf the next spring. The caterpillars become full 

 grown in three or four weeks, when they pupate just beneath 

 the surface of the soil, and two or three weeks later the 

 moths emerge. 



Control. Hellebore is not as effective as against the saw-fly 

 larvae and as the larvae usually appear before the fruit is setting, 

 they may be better controlled by spraying with arsenicals. When 



FIG. 351. The currant span-worm (Cymatomorpha riberia Pitch): 1, 2, larvae; 

 3, pupa; a, egg; b, eggs on twig; c, moth a, much enlarged, others 

 natural size. (After Saunders. ) 



the caterpillars are disturbed they drop from the foliage, letting 

 themselves down by a silken thread and remaining suspended in 

 mid-air until danger is over, when they reascend'the thread. 

 This habit may be utilized for their destruction by jarring the 

 bush so that they will drop, and then passing a forked stick around 

 it so that all the threads may be caught and the caterpillars may 

 be drawn out in groups and crushed with the foot. 



