10 BULLETIN 1223, U. S. DEPARTMENT OF AGRICULTURE. 



In the autumn, when the leaves begin to fade and fall, these larvae 

 move to more permanent places, locating in the crevices of the bark 

 on the twigs and branches (PI. IV, A) and clustering about the win- 

 ter buds, where they spend the winter. Some of the larvae fail to 

 move from the leaves before these fall from the trees, and are carried 

 considerable distances by the wind. Some of these die from starva- 

 tion, while others crawl up the trunks of near-by trees to new feeding 

 grounds. 



The first-stage larvae excrete very little wax, but the second-stage 

 larvae are well covered with sugary-appearing particles of it. This 

 protects them in the winter from frost and rain and incidentally 

 makes them immune to any mild form of spray material. 



The larvae remain in the second stage for from six to seven months, 

 or from late summer to late winter or early spring. The male larvae 

 are the first to leave their winter quarters. In fact, some of them 

 do not wait for winter to end, for on the first mild days in late 

 January they begin to form their cocoons in which to pupate. They 

 seem to be particularly fond of making their cocoons (PI. IV, B) on 

 dead twigs or branches, in the bark crevices, or near the crotches of 

 living limbs. Their cocoons may even be found massed together in 

 large white patches (PL V, B) on smooth exposed parts of the trunk 

 or branches. 



ACTIVITIES OF THE MALE. 



The cocoon is made of waxy threads, secreted from the pores on 

 the body'of the larva. These are woven and twisted about until a 

 definite covering has been formed. After completing the cocoon, 

 which requires several days, the larva changes to a prepupa, which is 

 the first dormant stage in the transformation from larva to adult. 

 A definite molt takes place at this time, the cast skin being pushed 

 out through a slit in the rear end of the cocoon. 



A week or so later another molt occurs, this time to a true pupa, 

 the second cast skin being pushed back out of the cocoon. (PI. VI, 

 5.) This stage occupies from one to two weeks, whereupon the pupa 

 changes either to a winged (PL VI, 4) or a wingless (PL VI, £, 3) 

 adult male. All the first pupae to transform become wingless males, 

 while all the last become winged males. During part of the inter- 

 vening time both winged and wingless adults can be found, together 

 with different forms between these two extremes. For instance, 

 some males will have partly formed to nearly fully formed wings, 

 while the wax anal filaments may vary from partly formed to full 

 length or even be entirely lacking on either extreme. Temperature 

 and humidity probably cause these variations. E. P. Felt (7), of 

 New York, reports a definite period occurring- between the appear- 

 ance of the two forms of the adult male in the State. There is no 

 such period in the West. 



The wax filaments may be seen protruding from the cocoons for 

 a day or so before the males emerge (PL VI, 1), which they accom- 

 plish by backing out. They live only a few days, dying soon after 

 they mate. 



