THK WllITK .MARKKI) TLSSOCK MOTH 69 



paint brushes, and just behind these are two red tubercles. The 

 young caterpillars are hairy and only about 16 of an inch in length. 

 They often spin a silken thread by means of which they lower them- 

 selves upon a sudden jarring of the tree. Being very light they are 

 readily blown at this time to neighboring trees, hence spreading 

 the infection. These young caterpillars feed only on the epidermis 

 of the leaf, but as they get older more and more of the leaf is eaten 

 until when full grown all the leaf is eaten but the midrib and per- 

 haps a few of the larger veins. It takes five to six weeks for the 

 caterpillars or larvae to mature. At the end of this stage they begin 

 to wander over the tree and from tree to tree looking for a place 

 suitable for pupation. When found the larvae spin cocoons in 

 which many of the hairs of the body are interwoven. About a fort- 

 night is spent as pupae in these cocoons. 



ADULTS. 



About the first part of July the adults make their appearance. 

 The females are wingless creatures and rarely ever leave the 

 cocoons until the eggs are d,eposited, after which they die. The 

 males are beautiful little moths with delicate feathery antennae and 

 hairy legs. The wings are marked with several shades of gray and 

 have a wing expanse of nearly one inch. 



EGGS. 



The eggs are laid on the discarded cocoons of the female in 

 masses each containing from one hundred to five hundred eggs. 

 A frothy white secretion covers and binds the eggs in a solid mass. 



HIBERNATION. 



The eggs in these conspicuous white masses remain over win- 

 ter. About the last of May and the first of June the eggs hatch and 

 the young begin feeding on the leaves. 



CONTROL. 



Fortunately there are a large number of predacious and para- 

 sitic insects that prey upon the Tussock Moth and often keep it in 

 check. Fungous and bacterial diseases also play a part. In some 

 years, however, conditions are not favorable for the development of 

 these forms and the Tussock caterpillars become abundant and do 

 considerable damage. Of the hundreds of egg masses that we have 

 examined at the present time, the great majority of the eggs appear 

 to be perfectly healthy, and unless these enemies are very abundant 

 during the early stages of the caterpillars great damage may be 

 looked for in June, 1917. 



