358 



Ha^idbook 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 mana^res 

 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 

 roll a stitt leaf is hard to solve. I, myself, beheve it is done by makino- 

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

 several species working, and the leaf conies 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 



outhne. 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 dilficult 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 hv 



the bassivood 



leaf-roller. 



Comstock. 

 Manual. 



