THE NYMPHS 



story of a caterpillar of this latest brood is very 

 interesting. It feeds on the tip of the leaf as de- 

 scribed, but when about one-third grown it chooses 

 a leaf and eats from the top about a third the way 

 down. It then fastens the petiole of this leaf to 

 the twig so that it will surely stay all winter ; 

 then covering the upper surface of the leaf with 

 a film of silk it draws it together lengthwise 

 above itself, making a tube just large enough to 

 hold its precious person ; it then lines this tube 

 with silk. This is its winter home, and when done 

 the caterpillar crawls into it head first, the warty 

 last segment of the body fitting nicely the open- 

 ing and making a living door ; and there it re- 

 mains until the first buds of spring call it out to 

 a vernal breakfast. 



In case of the species which are two-brooded 

 the question is, How does this caterpillar know 

 how to make this winter house? It does it while 

 the summer is still warm, sometimes in August 

 when there is no suggestion of cold or winter 

 fasting. Its parents made no such house, and if 

 it inherited the habit it must have been from its 

 grandparents. This is one of the many mysteries 

 of butterfly life which we with our coarse senses 

 are not likely to fathom. 



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