oj4 



Marvels of Insect Life, 



window frames, usually with the head upwards, but sometimes horizontallv. They 

 spin a little patch of silk in which to hook the tail of the chrysalis, and a loop of the 

 same material to keep the fore-part of the body steady. In this position they 



throw off the last caterpillar skin and 

 become keeled and angled chrysalids 

 of a g■reenish-^^'hite or whitish-grev 

 colour, liberally dotted with black and 

 streaked with yellow. 



At this point we ought to say that 

 there are two broods of the Insect in 

 each year. We will suppose that the 

 Insects we have been describing came 

 from eggs deposited in May. The 

 chrysalis stage is reached at the end 

 of June. In July the butterflies will 

 be la3dng fresh batches of eggs, and 

 these will produce chrysalids by Sep- 

 tember. These chrysalids will remain 

 as such until the following spring. 



Fortunately for the cottager and 

 the market gardener many of the 

 caterpillars never reach the chrysalis 

 stage, and many chrysalids fail to 

 produce butterflies. The caterpillars 

 are stung by a minute ichneumon- 

 wasp, which lays numerous eggs in its 

 body, for such creatures take no 

 account of the warning colours or 

 objectionable smells that keep off 

 larger enemies. The ichneumon-grubs 

 feed upon the interior parts of the 

 caterpillar, and when it is about to 

 become a chrysalis they make their 

 way out through the skin, and spin 

 minute cocoons for their own pupation. 

 The caterpillar dies exhausted. But if 

 the caterpillar has evaded this deadly 

 enemy and become a chr3/salis, it may 

 be immediately set upon by a much 

 smaller member of the same order of 

 four- winged stinging Insects, who may 

 load it with more than a hundred eggs, 

 and these hatching consume the whole 

 of the material that should have gone 

 to the evolution of the butterfly. The 



Pi'<'to by] [Hu:'Ji MtiiH, F.E.S. 



A Butterfly's Eggs. 



'I'his cluster of eggs of the large white butterfly, deposited upon a 

 rabbage-leaf, shows the eggs enlarged to twenty times the natural 

 size. This is the first stage in the cycle of butterfly development. 

 From each of these emerges one of the tiny caterpillars that arc 

 shown on the page opposite. 



