INSECTS AFFECTING PARK AND WOODLAND TREES IIQ 



lying among a few threads and securely attached to them by its terminal 

 spine. 



The male and female moths differ markedly. The former, a slender 

 olive brown, blacic marked creature with featherlike antennae and having 

 a wing spread of about lyi inches, may be seen flying in the late afternoon 

 and early evening in considerable numbers. It is represented with wings 

 expanded at figure 13, plate 9. The female is much heavier and lighter 

 colored. She has a wing spread of about 2 inches and is a white or buff 

 white color with more or less distinct black markings. The abdomen is 

 tipped with buff. The female in her characteristic resting position is well 

 shown at figure 14 on plate 9. The female moth does not fly though she 

 apparently has well developed wings. 



Life history. The winter is passed in the (tgg mass, which is remark- 

 ably resistant to atmospheric and other agencies. Experiments have 

 shown that even when the egg clusters were broken up and freely exposed 

 to the elements, the eggs were apparently not harmed, and a normal 

 proportion of the caterpillars appeared at the usual time, which in the 

 vicinity of Boston is from the last of Api^il to the middle of June. The 

 feeding period extends from the first of May to about the middle of July, a 

 caterpillar requiring from about 9 to 1 1 weeks to complete its growth and 

 enter the pupal stage. The young caterpillars remain on the egg clusters 

 from one to five or more days and then commence feeding on the leaf 

 hairs. Soon they eat out small holes in the leaves and, after the third or 

 fourth molt, about as many feed on the edge of the leaf as eat out holes. 

 The caterpillars are largely nocturnal, remaining in clusters on limbs and 

 trunk or hiding in some crevice during the day, and beginning between 

 7 and 8 o'clock in the evening leisurely to ascend the tree, where they 

 feed on the foliage at intervals during the night, descending about 3 o'clock 

 in the morning. Many of our farmers are familiar with the masses of 

 forest tent caterpillars so abundant in sections of New York the past two or 

 three years. The gipsy moth caterpillars assemble in just such masses, and 

 on badly infested trees they are as destructive as our native species. 



