DAMAGE CAUSED BY ANIMALS. 195 



The Spruce Cervicorn, Callidium luridum. This is in reality a 

 much more injurious species of cervicorn than any of the above- 

 mentioned beetles, but it chiefly attacks conifers (the Spruce in 

 particular) that are in a sickly or already damaged condition. 

 The larvae feed first of all in the cambial layer, and thus kill the 

 stem before they bore deep into the wood. Next to Pissodes 

 hercynise this was the species of beetle most numerous in the 

 damaged Spruce forests of Bavaria in 1890, after the Spruce 

 moth (Liparis monacha) had begun its ravages (vide foot-note on 

 page 88). It is mentioned here, as no special paragraph was con- 

 sidered necessary for coniferous cervicorns. Immediate felling 

 and removal of stems attacked should take place so soon as the 

 insects are recognised by the outpouring of resin, and the gradual 

 withering of the crown of foliage. Its generation is biennial. 



95. Weevils, or Rostral or Proboscid Beetles (Curculionidte). 



Of this rather numerous family a comparatively small number 

 of very injurious species attack conifers (vide pars. 75 to 77), but 

 the great majority of weevils feed on plants of broad-leaved 

 foliage, and not a few of them on our forest trees. 



In some cases damage is done by the larvse, which live in the 

 interior of the plants and destroy their tissue, whilst in others 

 the main injuries are inflicted by the beetles devouring buds, 

 flowers, and foliage ; but concerning their full life-history our 

 knowledge is by no means yet complete. 



The characteristic feature of the Curculionidte is the elongation 

 or extension of the head to form a rostrum or proboscis, by 

 means of which the majority of the species are easily recognisable. 



The so-called green and grey rostral beetles are especially 

 destructive in young plantations and nurseries, where they often 

 commit considerable havoc. These species are characterised and 

 distinguishable by a kind of greenish or greyish metallic lustre, 

 and among them the following are of most frequent occurrence : 



1. Having a Greenish Metallic Sheen. 



The Silvern-green Rostral Beetle, Curculio (Phyllolius) argentatus. 

 This beetle gnaws and destroys the buds on Beeches, Birches, 

 and Oaks. It is blackish in colour, with emerald or bluish-green 

 lustrous scales ; the elytra have whitish hairs, and the feelers and 

 legs are brownish-yellow. Only 0*2 to 0*24 inches in length. 



