310 PROTECTION AGAINST INSECTS. 



The caterpillars, enclosed in their common web-nest, first 

 gnaw the upper side of the leaves. Next spring, after 

 renewing their nests, they feed on the buds and young leaves, 

 and later, on the blossoms and fully developed leaves, except 

 the petiole. In this way, the fruit is considerably reduced in 

 quantity, if not entirely destroyed. Up to the middle of May, 

 in bad weather and also during the night, they retire to their 

 nests. After the third moulting, at the middle or end of May, 

 they abandon their nests, and wander among the trees to 

 feed. 



The crowns of the trees which are attacked begin about the 

 end of August to look as if they had been singed by fire ; 

 later, the woods become more or less completely defoliated. 

 If defoliation takes place before Midsummer a second foliage 

 may appear. 



d. Protective Rules.- 



Protection of enemies. Titmice and the cuckoo are very 

 useful. 



Cutting off the caterpillar nests with shears, and burning 

 them. 



Collecting and killing the caterpillars in May, and the pupae 

 in June. Care must be taken to protect the hands against the 

 hairs, which cause inflammation. The above measures should 

 be adopted for orchard and avenue trees. 



5. Liparis monacha, L. (Black Arches, or Nun Moth), 

 a. Description. 



The moth has a spread of wings of 40 mm. ( $ ), up to 50 mm. 

 (?). Fore-wings white, with many black zigzag transverse 

 lines and patches, hind-wings light grey ; abdomen with broad, 

 rose-red bands, separated by black bands, which are very well 

 marked in the $ . 



The caterpillar is 40 to 50 mm. long, with 16 legs, hairy, 

 tapering slightly towards the tail, reddish-grey above and 

 greenish-grey below ; with 6 bluish warts bearing tufts of long 

 hairs on each segment, and on the 6th a velvety-black heart- 

 shaped spot. 



