CHRYSOMELA POPULI. 



285 



later, new jbeetles 10 days later. Fresh larvae in August, the 

 second generation closing in the middle of September. Locally 

 common in many parts of the British Isles, chiefly in South 

 England. 



c. Relations to the Forest. 



The insect, both in the larval and beetle stages, attacks 

 young poplars and sometimes aspen shoots. Occasionally 

 they are found in osier-beds, especially on Salix pur- 

 pur ea, L., and S. pen- 

 tandra, L., and to a 

 less extent on S. rubra, 

 L., etc. The larvae 

 attack the leaves, which 

 are completely skele- 

 tonised, the parenchyma 

 being eaten and the 

 veins left intact. The 

 imago eats holes out of 

 the leaves. 



The attacks last from 

 June to August. 



Fig. 143. C. populi, L. 

 a Leaf bitten by beetle, b Leaf bitten by larvae. 



d. Protective Rules. 



Collection of the 

 beetles on to cloths by 



beating the trees in May and June, and again in August to 

 September. 



C. tremulae, Fabr., is somewhat smaller than, and greatly 

 resembles the above species, but has no black tips to its elytra. 

 It is the more destructive of the two, sometimes completely 

 destroying the foliage and shoots of young aspen. It also 

 attacks osier- willows, especially Salix purpurea. 



2. Chrysomela vidgatissima, L. (Willow Beetle).* 

 a. Description. 



Beetle 4 to 5 mm. long, oblong-oval, of a bronze or green 

 .tint, sometimes coppery or indigo-coloured, violet or black. 



* Vide Miss Ormerod, op. cit., pages 270 to 276. 



