144 BRITISH BUTTERFLIES 



it constructs its web and silken cord as already described (page 36), 

 and then changes to a bluish-white chrysalis, dotted with black. 

 The butterflies of the summer brood emerge shortly after, but 

 the chrysalides of the next brood hybernate till the following 

 spring. 



It is remarkable that we are so plagued with ' Whites ' seeing 

 that they have so many enemies. Many of the insect-feeding birds 

 commit fearful havoc among their larvae, and often chase the 

 perfect insects on the wing, but perhaps their greatest enemy is the 

 ichneumon fly. 



Look under the ledges of a wall of any kitchen garden, and you 

 will see little clusters of oval bodies of a bright yellow colour. 

 Most gardeners know that these are in some way or other 

 connected with the caterpillars that do so much damage to their 

 vegetables. They are often considered to be eggs laid by the 

 larvae, and are consequently killed out of pure revenge, or 

 with a desire to save the crops from the future marauders. 



No greater mistake could be made. These yellow bodies are 

 the silken cocoons of the caterpillar's own foes. They contain the 

 pupae of the little flies whose larvae have lived within the bod} T of 

 an unfortunate grub, and, having flourished to perfection at the 

 expense of their host, left its almost empty and nearly lifeless 

 carcase to die and drop to the ground just at the time when it 

 ought to be working out its final changes. Often you may see the 

 dying grub beside the cluster of cocoons just constructed by its 

 deadly enemies. Should you wish to test the extent of the 

 destructive work of these busy flies, go into your garden and collect 

 a number of larvae, and endeavour to rear them under cover. The 

 probability is that only a small proportion will ever reach the 

 final state, the others having been fatally ' stung ' before you took 

 them. 



The Small White (P. Rapce) 



This butterfly closely resembles the last species except in point 

 of size. The male, represented on Plate I (fig. 4), has a dark grey 

 blotch at the tip of each fore wing, a round spot of the same colour 

 beyond the centre of that wing, and another on the costal margin 

 of the hind wing. The female may be distinguished by an 

 additional spot near the anal angle of the fore wing. 



Although this and the two other common butterflies (Brassicce 

 and Napi) that frequent our kitchen gardens are usually spoken of 



