NATURAL HISTORY OF SOUTH AFRICA 



weight is 11,312 times as great as when it was 

 born. 



A caterpillar on an oak tree was kept under obser- 

 vation for fifty-two days, and during that period it 

 ate 120 oak leaves weighing three-quarters of a 

 pound. 



We all know what a greedy feeder a silk-worm 

 is. It can be taken as an example of the eating powers 

 of other species of caterpillars. Is it, therefore, not 

 essential for us to carefully foster and care for all 

 enemies of caterpillars ? If, as an instance, a bird 

 had gobbled up the caterpillar referred to on the oak 

 tree, 120 oak leaves would have been saved. When the 

 caterpillar is full grown it ceases eating. If it is the 

 larva of a moth it will spin a cocoon of silk or make 

 a bag of some sort around itself, or else hide away 

 amidst decaying leaves or loose mould and change 

 into a chrysalis. If it is the larva of a butterfly it will 

 probably suspend itself from a twig or crawl into cover 

 and change into a chrysalis. The chrysalis of a 

 butterfly caterpillar is usually golden in colour, whereas 

 that of the moth is deep reddish-brown. 



The caterpillar or larva has now turned into a 

 chrysalis or pupa. It lies sleeping in its case for 

 some days, weeks, or months, according to the species 

 of insect and the weather. Suddenly the chrysalis 

 opens, the top ring lifting off like a lid, and a moth 

 or butterfly crawls out. In the interval of sleep the 

 ugly caterpillar has changed into a lovely moth or 

 butterfly. The insect is now called an imago, and 

 is as big as it ever will be. At first it is weak and 



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