284 PROTECTION AGAINST INSECTS. 



leaves. Some species are very injurious, both the imago and 

 larva eating the leaves of broadleaved trees. 



1. Chrysomela populi, L. (Red Poplar-leaf Beetle). 



a. Description. 



Beetle 10 to 12 mm. long, of an obovate shape, blackish-blue, 

 the elytra brick-red, their extreme tip black ; thorax narrower 

 than the elytra, its sides rounded, broadly raised and coarsely 

 punctured; antennae short, compressed, thickened towards 

 the ends. 



Fig. 142. C/tri/.iomeZa populi, L. 

 a Beetle. I Larva, c Pupa. 



Larva 6-legged, of a dirty white colour, with many black 

 spots, and two white lateral projections on the 2nd and 3rd 

 segments. 



Pujja sharply narrowed towards the posterior extremity, 

 brownish yellow, with regularly distributed black spots and 

 stripes. 



I). Life-history. 



The season for flight is in May and June. 



The ? lays her yellowish-white eggs in clusters of 10 to 12, in 

 all 100 to 150, on the under-side of the leaves of young poplars. 



The larvae emerge in June or July, feed openly on the leaves, 

 and if disturbed exude a milky-white fluid, with an odour of 

 bitter almonds. 



Pupation takes place in July and August ; the pupae hang 

 reversed from the leaves by their pointed end. 



The beetles emerge by the end of August, and after October 

 hibernate under leaves or moss, reappearing in the open in 

 April. 



Generation annual, but frequently double, when the beetles 

 hibernate ; larvae appear in May and June ; pupae 3 4 weeks 



