358 



Handbook of Nature-Study 



is that the soft -bodied caterpillar may eat its fill completely hidden from 

 the eyes of birds or other animals. When it first hatches from the egg, it 

 feeds for a short time, usually on the under side of the leaf; but when still 

 so small that we can barely see it with the naked eye, it somehow manages 

 to fold over itself one edge of the leaf and peg it down. The problem of 

 how so small a creature is able to pull over and fold down or to make in a 

 rollja stiff leaf is hard to solve. I, myself, believe it is done by making 

 many threads, each a little more taut than the last. I have watched 

 several species working, and the leaf comes slowly together as the cater- 

 pillar stretches its head and sways back and forth hundreds of times, 

 fastening the silk first to one side and then to the other. Some observers 

 believe that the caterpillar throws its weight upon the silk, in order to 

 pull the leaf together ; but in the case of the sumac leaf-roller, I am sure 



this is not true, as I have 

 watched the process 

 again and again under a 

 lens, and could detect 

 no signs of this method. 

 Many of the caterpillars 

 which make rolls, change to 

 small moths known as 

 Tortricids. This is a very large 

 family, containing a vast number 

 of species and not all of the 

 members are leaf-rollers. These 

 little moths have the front wings 

 rather wide and more or less rectangular in 

 outline. The entomologists have a pleasing 

 fashion of ending the names of all of these 

 moths with "ana;" the one that rolls the 

 currant leaves is Rosana, the one on 

 juniper is Rutilana, etc. Since many of the 

 caterpillars of this family seek the ground to 

 pupate and do not appear as moths until the 

 following spring, it. is somewhat difficult to 

 study their complete life histories, unless one 

 has well-made breeding cages with earth at 

 the bottom; and even then it is difficult to 

 keep them under natural conditions, since in 

 an ordinary living room the insects dry up 

 and do not mature. 



A leaf of 

 bassivood cut 

 and rolled by 

 the basswood 

 leaf-roller. 



Comstock. 

 Manual. 



