NATURAIv ENEMIES OF THE FOREST. 



247 



S«5^iia*«Sa5iu,,^2 



tig- 111 Wutl of the Columb an Limb r beetle 

 lulp^\ood Cal o P plir [1^;-/ 1 J I 

 1 J, rit. 40, 1 J I 



pests. The most destnietive are the pi'edaceons and parasitic insects 

 Man)' insects are simply predaceons, pouncing upon and destroying 

 sucli other insects as tliey can overcome. 

 Still others are parasites^ some external, 

 but most of them living within the bod- 

 ies of their victims where they pass their 

 entire larval life. The eggs are laid on 

 or in the body of the victim, so that as 

 soon as one hatches, it has suitable food. 

 The ichneumon fly. Fig. 103, is such a 

 parasite; it destroys millions of insect 

 pests. It has a long and peculiar ovipos- 

 itor with which it drills a hole into the 

 tree and deposits the egg in a burrow of 

 the Pigeon Horntail, a wood wasp that 

 burrows into deciduous trees. The lai'va 

 soon finds its victim, the grub of the 

 Pigeon Horntail, and lives on it to its 

 destruction. 



It Avould seem that it is a hopeless 

 task to control the insect enemies of for- 

 est trees and forest products or to pre- 

 vent losses from their ravages, but the 



writer is informed by Dr. A. D. Hopkins, Fisr. 102. vvoru-of the carpen- 

 ter Bee, Xyiocopa orpt'fex, in 



the expert in the Bureau of EntomoloSV Redwood Cumber: a,entrance; 



l'^ M^aUeries; c, cells; t/, larva; 



in chai'tre of forest insect investigations, .■, aduit. \Agrk. Tear Book, 



^ " ' 1")04, Fig". 53, p. 390.1 



