64 



The eggs, figure 48, a, are laid on the under side of the leaf, 

 where, if all is favorable, they hatch in about a week into hairy, 

 yellowish black larva;, figure 48, b. g. This is in May, or early 

 in June. The larva grow brighter in color, as they grow older. 

 When fully grown they are about half an inch long, and of the 

 form shown in the figure. As seen in the enlarged sections, shown 

 at h. and /., the hairs are in tufts. Beside the yellow band along 

 the back, there is a similar one along each side. The head is 

 mostly black. After hatching, the larva at once begin to feed 

 upon the leaves, eating out the pulp, leaving the woody framework 

 as seen in figure 48. They continue feeding only about two 

 weeks, but as the eggs do not all hatch at once, the trees may be 

 infested by them at any time from May to August, although the 

 length of the time during which they feed would vary with season 

 and temperature. When fully grown the larva go to the ground 

 and change to pupae. According to Riley, the pupa stage lasts 

 from six to ten days. This insect bids fair to become one of the 

 most dangerous foes of the elm. Concerning its ravages in New 

 York, Dr. Lintner remarks, Fourth Report of State Entomologist, 

 263 : " During the last few years it has extended its ravages to 

 Long Island and Westchester County, N. Y., where by its com- 

 plete defoliation of large and beautiful elms, and by the myriads 

 of the disgusting larvae swarming on the trunks of the trees, it 

 became a common object of observation and execration." It has 

 been gradually working its way northward, and though not yet a 

 pest in Vermont, it does occur here, and may easily become a 

 serious pest. The beetle has been carefully studied at the Depart- 

 ment of Agriculture, and figure 48 is taken from one drawn by 

 Dr. Riley. The insect has sundry enemies among beetles, which 

 keep it in check to a certain extent. Plowing the ground under 

 infested trees when the larva are in the ground, thus exposing 

 them to birds or swine, which should be done after the first of 

 August, is to be reconmiended. Spraying the infested trees, has 

 on the whole, proved most useful, and has, I believe, uniformly 

 produced good results. The mixture which, after very numerous 

 experiments by different persons in different parts of the country, 

 seems best, is the following : Three-eighths pound London purple ; 

 three quarts flour ; forty gallons of water. 



The object of the flour is to render the liquid more adhesive so 

 that it does not so readily wash oft from the leaves and twigs. In 



