8 
through Ohio, Indiana, Kentucky, Tennessee, and other Western 
States.! 
Food plants.—No food plants other than elms are known. The com- 
mon English elm (Ulmus campestris) is its favorite food, and the gar- 
dener’s variety, the so-called Camperdown, or weeping elm, is attacked 
with equal avidity. The American, or white, elm (U. americana) ranks 
next among the favored species, with U. montana, U. suberosa, U. flava, 
U. racemosa, and U. alata in about the order named. No variety seems 
absolutely exempt. In the presence of U. campestris other elms are 
seldom seriously injured. Where campestris is absent, or where a 
single tree of campestris is surrounded by many American elms, the 
latter become seriously attacked.’ 
Life history and habits.—The elm leaf-beetle passes the winter in the 
adult, or beetle, condition in cracks in fences or telegraph poles, under 
the loose bark of trees, inside window blinds in unoccupied houses, in 
barns, and, in fact, wherever it can secure shelter. As soon as the 
buds of the trees begin to swell in the spring, the beetles issue from 
their winter quarters and mate, and as soon as the buds burst they 
begin to feed upon the leaflets. 
This feeding is continued by the beetles until the leaves are fairly 
well grown, and during the latter part of this feeding period the females 
are engaged in laying their eggs. The eggs (fig. 3, c) are placed on 
the lower sides of the leaves, in vertical clusters of 5 to 20 or more, 
arranged in two or three irregular rows. They are elongate oval in 
shape, tapering to a rather obtuse point, orange yellow in color, and 
the surface is covered with beautiful hexagonal reticulations. These 
reticulations, however, can be seen only with a high magnifying power. 
The egg state lasts about a week. The larve (fig. 3, d) as soon as 
hatched feed on the under surface of the leaf, gradually skeletonizing 
it. They reach full growth in from fifteen to twenty days, and then 
either crawl down the trunk of the tree to the surface of the ground or 
drop from the extremities of overhanging branches. At the surface of 
the ground they transform to naked, light orange-colored pup (fig. 
3, 9), a little over a quarter of an inch in length, and in this stage they 
remain for from six to ten days, at the expiration of that time trans- 
forming to beetles. The pup will frequently be found collected in 
masses at the surface of the ground in this way. On very large trees 
with shaggy bark many larve will transform to pupe under the bark 
scales, or on trees of the largest size they may descend the main 
' Since this was written the writer has learned that this passage of the Blne Ridge 
barrier has actually taken place during the past season. Mr. A. D. Hopkins, of the 
West Virginia Agricultural Experiment Station, has found that this insect has 
established itself at Elmgrove, in Ohio County, and at Wellsburg, in Brooke County, 
W. Va. 
2The beetles rarely oviposit upon Zelcova carpiniafolia and Z. acuminata on the 
Department grounds at Washington. 
—— 
