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NATURE-STUDY REVIEW [15:7— Oct., 19 19 



Leaf roller in sumac, with diagram showing the 

 fastening of the silk slay ropes 



The Leaf Miners 



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 fol- 

 lowing 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 condi- 

 tions, since in an 

 ordinary living room 

 the insects dry up 

 and do not mature. 



In every leaf, however, thin, there are rows of cells containing 

 the living substance of the leaf, with a wall above and a wall 

 below to protect them. Some of the smaller insects have dis- 

 covered this hidden treasure, which they mine while safely pro- 

 tected from sight, and thus make strange figures upon the 

 leaves. 



Among the most familiar of these are the serpentine mines, 

 so called because the figure formed by the eating of the green 

 pulp of the leaf, curves like a serpent. These mines are made by 

 the caterpillars of tiny moths, which have long fringes upon the 

 hind wings. The life story of such a moth is as follows : The little 

 moth, whose expanded wings measure scarcely a quarter of an 

 inch across, lays an egg on the leaf; from this, there hatches 

 a tiny caterpillar that soon eats its way into the midst of the 

 leaf. In shape, the caterpillar is somewhat "square built," 



