The Grape-Berry Moth. 109 



in cocoons on the fallen grape leaves. The loose bark on the vines 

 or trellis posts affords ideal places for hibernation, but after several 

 hours careful searching in such places in a badly infested vinej^ard in 

 the autumn of 1903, we failed to find a single grape-berry moth. 

 But we did find quite a number of the pupae in their characteristic 

 cocoons on the fallen leaves beneath the vines. This divergence in 

 the hibernating habits in the two coimtries was easily explained 

 when further study revealed the fact that the American grape-berry 

 moth is not the European insect with similar habits, although very 

 closely related to it. 



The winter is always passed in the pupa state in the cocoon. We 

 found most of the cocoons in the autumn on the damp and decaying 

 leaves close to the ground under the vines, rather than on the drier 

 leaves which are often blown into piles. There were also indications 

 that some of the cocoons soon break away from the decaying leaves. 

 These facts may explain why some have failed to breed the moths 

 from leaves collected, probably from convenient piles in vineyards. 

 In our breeding cages in autumn all the caterpillars spun their cocoons 

 on the grape leaves rather than on the pieces of grape-vine, except 

 one which cut its peculiar cocoon from a thin flap of the bark. 



Appearance and work of the spring brood. — In a cage of hibernating 

 pupae that we kept outdoors, no moths appeared in the spring, and 

 the pupae got mouldy. But from pupae kept in the warm insectary 

 all winter, the moths were doubtless forced and began to emerge 

 March 19 and continued until April 14. Thus we missed the normal 

 time of emergence of the moths in the spring, but as recently-hatched 

 caterpillars were found at work in the vineyards on June 17, some 

 of the moths are doubtless flying by June 1, in the Chautauqua region. 

 The eggs laid by these moths were not observed, but they are probably 

 stuck on the stems of the blossom clusters. 



Some of the caterpillars hatch and begin feeding before the grape 

 blossoms open. They make a slight web among the blossom buds 

 into which they eat, oftentimes destroying a dozen or more embryo 

 grape-berries. The destructive work of this spring brood of cater- 

 pillars continues in June through the blossoming period and among 

 the recently set berries, as shown in Figs. 17 and 19. 



One caterpillar may destroy more developing fruits in June than 

 half a dozen caterpillars working in the larger berries later in the 

 season. Yet this spring brood of the grape-berry moth and its work 

 rarely attract attention. This is doubtless largely because the 

 slightly webbed portions of the clusters of blossoms or young fruits 

 do not make infested clusters especially conspicuous, and the spring 



