ENEMIES OF APHIDES. 



263 



or groups on leaves, or in many cases underneath bark, and pro- 

 bably, I think, in this latter situation survive the winter, though, 

 as I have seen specimens of Capsus hybernating in December and 

 January, there can be no doubt that some of the mature insects 

 survive until spring to perpetuate their race. 



The highly destructive system of the insect world is well seen 

 in the vast proportion of the eggs of bugs which are pierced and 

 destroyed by parasitic Hymenoptera. So much is this the case 

 that it is very uncertain if a cluster of eggs will yield a single 

 Heteropteron larva, their place being taken by minute Hymenop- 

 tera of similar species to those which we shall later on review as 

 the chief destroyers of Aphides. 



EXPLANATION OF PLATES XIII. AND XIV. 



Plate XIII. 

 Fig- 1 • — Imago of Plagio7iathus arbustorum. 

 2. — Larva of Anthocoris sylvestris. 

 3. — Ima^o of same. 



Plate XIV. 



Fig. 1. — Antenna of Plagionathus arbustorum. 



,, 2. — Hemelytron of same. 



J, 3. — Tibia and tarsus of same, exhibitina; characteristic 

 markings and spines. 



,, 4. — Antenna of Anthocoris sylvestris. 



,, 5, — Hemelytron of same. 



., 6. — Ovipositor of CVi^wiw lanarins, in situ (from a balsam 

 mcjunt). 



,, 7. — Ovipositor, separated. 



,, 8. — One of the external blades or sheaths. 



