21 



of oscillations in the numbers of the moths, in which periods of 

 destruction would alternate with periods of immunity. 



The later stages of the Gypsy moth are illustrated in ''the 

 accompanying figures. The male moths are much smaller than 



Fig. 17. Gypsy Moth Cg,terpillar. 



Fig. 18. Chrysalis of Gypsy Moth. 



the females. " The full grown caterpillar is about an inch and 

 three fourths in length, very dark brown or black, finely retic- 

 ulated with pale yellow. There is a pale yellow line along the 

 middle of the back and a similar one along each side. On the 

 first six segments following the head there is a bluish tubercle, 

 armed with several black spines on each side of the dorsal line, 

 and on the remaining segments these tubercles are dark crimson 

 red. In the middle of the tenth and eleventh segments there is 

 a smaller red tubercle notched at the top. The whole surface 



