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NATURE-STUDY REVIEW [15:7— Oct., 1919 



occur in sufficient numbers to injure the foliage of oiu* trees to any 

 extent; they simply help nature do a little needful pruning. All 

 of the moths are night flyers and are, therefore, seldom seen except 

 by those who are interested in the visitors to our street lights. 



The cocoons afford the most ready means of finding and rearing 

 these moths; they may be gathered during the months of Novem- 

 ber and December. They should not be kept in the hot and dry 

 schoolroom, but should be placed in boxes outside the windows 

 where they may have the moisture of the atmosphere and the 

 temperature which is natural to them. Cocoons kept thus should 

 be brought into the house early in April so that the moths may be 

 watched when emerging and captured for study. Miss Mary E. 

 Hill, who has had excellent success in raising cocoons kept in the 

 schoolroom all winter, dips them at least once a week in a dish of 

 water, letting them remain a few moments and thus keeping the 

 silk from getting so dry and hard, that the moths cannot push 

 their way out before their wings harden and cripple them. 



The reason we have chosen these silk-worms for the Review is, 

 that they are the most common and valuable subjects for nature- 

 study, and yet but few people know the species apart or know their 

 life histories. They illustrate well all of the phases of insect 



life, and the children never 

 tire of the miraculous appear- 

 ance of these magnificent crea- 

 tures as they issue from the 

 cocoons. 



The Cecropia {Samia 



cecropia) 

 This is the largest of our 

 giant silk-worms, the wings of 

 the moth expanding some- 

 times six and one -half inches. 

 It occurs from the Atlantic 

 Coast to the Rocky Moun- 

 tains. 

 Food Plants. — The caterpillars of this moth are general feeders 

 living on over fifty specimens of our common trees. They occur 

 very commonly on apple and plum trees and also on the wild 

 cherry. 



Ceropia eggs enlarged. 



