158 PROTECTION OF WOODLANDS. 



beetles swarm and fly about in May and June, the female deposits 

 her ova in small clusters in holes bored with the rostrum or pro- 

 boscis into the upper parts of the trees still retaining their smooth 

 bark. From this breeding-place as a centre, the larvae bore 

 sinuous and irregular radiating galleries in the cambial layer, 

 which increase in breadth as the larva increases in size, and 

 terminate in pupal chambers formed exclusively in the sap wood, 

 and filled up with bore-dust, within which the chrysalides rest. 

 Whether the generation occupies one year or two is not yet fully 

 determined. 1 The trees attacked soon fall into a sickly and 

 unhealthy state, and if much injured die off, whilst at the same 

 time these sickly stems offer considerable attraction as suitable 

 and favourable breeding-places for other noxious insects, bark- 

 beetles in particular. The white drops of resin, which exude from 

 the punctures made by the rostrum for the deposition of the ova, 

 betray to the practised eye the trees that have become attacked, 

 and when the beetle occurs in any great numbers, such stems 

 should be marked, felled, and barked an operation which must 

 be repeated from time to time throughout the summer. 



The Pine-pole Weevil or Rostral Beetle, Pissodes pinipliilus. 

 This beetle very much resembles, but is a little smaller than, 

 P. notatus. It is of a rusty-brown colour, with one characteristic 

 rusty-yellow patch on each of the elytra, and lives in the thin- 

 barked upper portions of Pine poles, although also to be found on 

 stems of older growth, where the female deposits her ova singly 

 in holes bored for the purpose. When the larvae come out, they 

 eat sinuous and very irregular galleries in the cambial layer, which 

 gradually increase in breadth, and at length terminate in small 

 pupal chambers formed in the sapwood, where the chrysalides rest. 

 The time of swarming is in June, so that the generation is eit 

 annual or extends over exactly two years, a point not yet det 

 mined. 2 This insect has hitherto not received very much attentic 

 although it sometimes occurs rather frequently. Poles and stei 

 that have been attacked sicken if at all badly injured, and ult 



1 Hess, op. cit., vol. i. page 267, states that it is annual as a rule, but that there 

 are exceptions and deviations from the rule. Altum says the generation occupies 

 two years, whilst Eichhoff assigns to it also a double generation. No Von Oppen has 

 as yet thrown the light of his observations on the subject. Trans. 



8 Here, again, Altum says it takes two years, and Eichhoff asserts that a double 

 generation takes place within the year. Hess (page 264) thinks an annual generation 

 is most probable. 





