726 Home Nature-Study Course. 



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

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

 needful pruning. All of the moths are night fiyers 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 November 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. Aliss Alary 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 a leaflet 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 appearance of these magnificent creatures 

 as they issue from the cocoons. 



THE CECROPi.\ (Saniia cccropia) 

 This 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 ]\Iountains. 



Food Plants. — The caterpillars of 

 this moth are general feeders living 

 on over fifty species of our common 

 trees. They occur very commonly on 

 apple and plum trees and also on the 

 wild cherry. 



Eggs. — The moth which issues 

 from the cocoon in the spring lays its 

 eggs upon the young leaves of the 

 tree on which the caterpillar is to 

 feed. The eggs are cream white, and 

 are laid in small clusters of short 

 Cecropia e^gs enlarged. ro^^'S- sometimes on the lower and 



sometimes on the upper sides of the 

 leaves. Just before hatching the eggs turn grayish ; they hatch from ten 



