COLEOPTERA. 



73 



trees do not suffer so severely, but they have been known to attack 

 young hardwoods, more especially when mixed with coniferous trees. 

 They eat the tender shoots, both bark and cambium, in such a manner 

 as to present an appearance of rabbit damage (fig. 72). In our 

 country the plants most used for planting are about three to four 

 years old, and when such are attacked after being recently planted it 

 is obvious they are not strong enough to resist the injuries, and the 

 consequence is that many die off, and expensive replanting has to 

 be resorted to. When the bark of older trees is eaten the injuries 

 are not so severe. The weevil is especially fond of young shoots, and 

 the vital cambium is therefore eaten with the bark. 



The beetle (fig. 73) is a dull black colour, but brightened by several 

 fairly large yellow spots on the elytra, which collectively form irregu- 

 lar bars. There are also a few yellow 

 scales on the thorax. The rostrum 

 is very stout, with the antennae in- 

 serted at the apex. Legs black, and 

 femora armed with a strong stout 

 spine. Length from 8 to 14 mm. 



As regards the life-history of this 

 insect, it affords a very striking con- 

 trast to the life -history of some 

 moths, as, for example, those which 

 appear and disappear within cer- 

 tain prescribed dates. The pine 



weevil may, with special entomological knowledge, be found in all 

 stages throughout the year. This fact, together with an unworked 

 life-history, led to great diversity of opinion. Thus Altum, who 

 carefully studied the species, maintained that a generation required 

 two years for its complete development, while Eichhoff considered it 

 more probable that there were two generations in a single year. This 

 point has now been decided by Von Oppen, who has done very 

 valuable work by working out its life-history from observations 

 carried on under circumstances approximating to its natural con- 

 ditions. As a result of his careful investigations, he found that the 

 beetle was endowed with great vitality (extending over two years), 

 and further, that it has the power of re-copulation and repeated egg- 

 deposition. Hence this would account for the insect being found in 

 all its respective stages at one and the same time. A single gener- 



Fig. 73. Hylobius abietis (pine weevil). 



a, beetle (natural size) ; 6, larva (natural 

 size); o, pupa (natural size). (From 

 ' The Forester,' by J. Nisbet.) 



