4 
surface in such a manner as to make a striking yellow carpet about 
the tree from a few inches to a foot or more wide. With very large 
elms, however, many of the larve are shaken off by winds or fall 
directly to the ground, sometimes fairly covering the surface over an 
area equal in diameter to the limb expanse-of the tree. 
Hibernation takes place in the adult state, both where there is but 
one brood and where there are two. For this purpose the beetles 
frequently enter houses and barns or outbuildings, sometimes assem- 
bling in such numbers that it is possible to collect them by the quart. 
They also enter cracks in posts, telegraph poles, fences, etc., or where- 
ever they can secure partial protection from winter storms. 
SUSCEPTIBILITY OF DIFFERENT ELMS. 
European elms seem to be especial favorites with this insect, and 
this would naturally be expected from its European origin. Its 
preference for the European elms is especially noticeable where these 
are grown in conjunction with American elms, the former being 
frequently entirely denuded, while the latter remain practically un- 
injured. In general, the coarser-leaved sorts of elms are distasteful 
to the beetles, and the smooth, thin-leaved varieties are especially 
subject to attack. The American species, Ulmus americana, is nota- 
bly exempt, and this, together with the general immunity of other 
American species, is a strong argument in favor of restricting planting 
to our native sorts. All species of elms, however, are attacked more 
or less, and in the absence of sufficient foliage of the favorite varie- 
ties the injury to less palatable sorts becomes almost equally marked. 
NATURAL ENEMIES. 
There are no effective American natural enemies of this insect. 
There exists in Europe an egg parasite which from time to time is 
very effective. This is a minute chalcidid, known as Tetrastichus 
xanthomelene Rond. After several years of fruitless effort this 
insect has been brought to the United States during the summer of 
1908 by Doctor Howard, through the kindness of Professor Valery- 
Mayét, of Montpellier, France, and has been distributed at Cam- 
bridge, Mass.; Melrose Highlands, Mass.; New Brunswick, N. J.; 
Ithaca, N. Y., and Washington, D. C. It bids fair to become a 
strong assistant in the fight against the elm leaf-beetle. 
REMEDIES. 
In nearly every stage of its life history this insect is easily sub- 
ject to treatment. The best means against the adults and larve 
consist in the use of arsenical poisons in the form of sprays on the 
[Cir. 8] 
