FOREST LIFE. 



217 



on the trunks of forest trees, in the wood of which the 

 larvae bore. Fig. 184 represents an adult horn-tail. 

 In this family the female has a long ovipositor, with 

 which she makes slender holes in the trunks of. trees 

 for the reception of her eggs. The horn-tails belong 

 to the family SIRICID^ (Si-ric'i-dae) of the order Hy- 

 menoptera. 



Among the more striking in appearance of the 

 insects found on forest trees are certain ichneumon- 

 flies that are parasitic on the larvae of the horn-tails. 

 These ichneumon- 

 flies bore holes into 

 the trees infested 

 by the horn-tails, 

 and lay their eggs 

 into the burrows 

 of the latter. The 

 larvagof the ichneu- 

 mon -flies fasten 

 themselves to the 

 horn-tail larvas, and 

 destroy them by 

 sucking their blood. 

 Fig. 185 represents 

 one of these ichneu- 

 mon-flies in the Fig. 185.— The hom-tail parasite laying an egg. 



act of laying an egg. These insects belong to the 

 family IcHNEUMONlD^ (Ich-neu-mon'i-dae) of the or- 

 der Hymenoptera. 



