BRITISH BUTTERFLIES 



its body and therein establish themselves as non- 

 paying guests. Caterpillars so commandeered often 

 succeed in attaining the chrysalis stage, but this prob- 

 ably only happens when the parasites are later than 

 their host in arriving at maturity. Although a large, 

 sometimes very large, percentage of caterpillars are 

 " ichneumoned," some certainly do escape the atten- 

 tion of these undesirables and other foes, and therefore 

 reach the chrysalis stage in a healthy condition. From 

 such chrysalides butterflies emerge in due course, the 

 whole period occupied in passing from egg to butterfly 

 not much exceeding six weeks in the summer-time. 



Some butterflies require the whole of twelve months 

 to effect the changes from egg to perfect insect, whilst 

 of others there will be three generations during the 

 year. Hibernating species such as the brimstone 

 and tortoiseshells are in the butterfly state for at least 

 six months, but they are in a dormant condition dur- 

 ing the greater part of that time. Even so their active 

 life is longer than that of the small copper, of which 

 there are three flights of butterflies in the year. The 

 duration of the caterpillar life is also a variable quan- 

 tity. In some kinds this stage is protracted over 

 several months, whilst in others it lasts only a few weeks. 

 Then as regards the chrysalis, some kinds remain 

 much longer in this stage than others. 



Down yonder lane, on the sunny side of the old barn, 



70 



