33 



Handbook of Nature-Study 



The cecropia moth. 

 Photo by M. V. Slingerland. 



THE CECROPIA 



Teacher's Story 



HE silk- worm which gives us the silk of com- 

 merce, has been domesticated for centuries in 

 China. Because of this domestication, it is 

 willing to be handled and is reared successfully 

 in captivity, and has thus come to be the source 

 of most of our silken fabrics. However, we have 

 in America native silk-worms which produce a 

 silk that is stronger and makes a more lustrous 

 cloth than does that made from the Chinese 

 species. But we have never had the time and 

 the patience, here in 'America, to domesticate 



these giant silk-worms of ours, and so they are, as yet, of no commercial 

 importance. 



The names of our common native silk- worms are: The cecropia, 

 promethea, polyphemus, and luna. In all of these species the moths are 

 large and beautiful, attracting the attention of everyone who sees them. 

 The caterpillars are rarely found, since their varied green colors render 

 them inconspicuous among leaves on which they feed. None of the 

 caterpillars of the giant silk-worms occur in sufficient numbers to injure 

 the foliage of our trees to any extent; they simply help nature to do a 

 little needful pruning. All of the moths are night flyers and are, there- 

 fore, seldom seen except by those who are interested in the visitors to our 

 street lights. 



The cecropia is the largest of our giant silk-worms, the wings of the 

 moth expanding sometimes six and one-half inches. It occurs from the 

 Atlantic Coast to the Rocky Mountains. 



