Insects, etc., Injurious to Nuts. 299 



week in August a second brood of moths appear. These soon pair, 

 and lay their eggs as before. If circumstances are favourable, a great 

 many eggs are laid, and the result, as we saw in 1906, is that the 

 leaves become covered with blisters in September. This second 

 brood of larvae reach maturity in early October. They then pupate 

 as before, and the moths hatch out and hibernate. At least, this is 

 what is apparent, for they have not been observed in any other 

 condition during the winter. 



I have failed to find any winter pup in the leaves, and yet all 

 the larvte pupated there. Those kept hatched out, and none could 

 be found in the leaves naturally. 



Unless I am much mistaken this is the normal way of wintering, 

 and thus we have another reason for separating this nut species 

 from Lithocolletis carpinicolella, which is found in the pupal stage in 

 the dead leaves of the hornbeam, which hang so readily on to the 

 trees during winter. The adult of L. carpinicolella is, however, very 

 like L. coryli. 



TREATMENT. 



This is very difficult, but I found a heavy spraying with arsenate 

 of lead used for Nut Weevil kept the trees clear of the first brood, 

 but that the second brood invaded the same trees from some old 

 cobs and filberts standing close by. 



A heavy spraying of arsenate of lead is undoubtedly good for 

 nuts if used in May; at this time the Winter Moth, Nut Weevil, 

 Leaf Weevils, and these Miners can all be attacked by it, and as it 

 holds on to the leaf well, later comers, such as the Croesus Sawfly 

 and the Buff-tip Moth, are also to some extent destroyed. 



THE NUT WEEVIL. 

 ^Balaninus mints. Linn.) 



This weevil is the parent of the maggot so frequently seen in nuts. 

 It is found in the filbert and cob and also in the wild hazel nuts. 

 Kaltenbach (3) refers to it on the oak. The filbert seems to suffer 

 from it more than the cob, but growers in Kent report it doing harm 

 to the latter. The damage is done by the maggots feeding in the 

 kernel and causing the nuts to fall prematurely, and also by spoiling 

 the samples owing to the repulsive appearance of the maggot found on 

 cracking the nuts. 



It occurs fairly widely over Britain where the hazel is abundant, 



