SHADE TREES AND THEIR INSECT DEFOLIATORS. 
FOUR PRINCIPAL LEAF-EATERS. 
There are four insects principally concerned in the defoliation of the 
shade trees in the city of Washington. They are: (1) The Imported 
Elm Leaf-beetle (Galeruca xanthomelena); (2) the Bag-worm (Thyridop- 
teryx ephemereformis); (3) the White-marked Tussock-moth (Orgyia 
leucostigma); and (4) the Fall Web-worm (Hyphantria cunea). 
THE IMPORTED ELM LEAF-BEETLE. 
(Galeruca xanthomelena* Schrank.) 
The depredations of this pest have now become widely extended 
throughout the Northeastern States, rendering almost worthless and 
unsightly those most valuable shade trees of our cities—the elms. As 
its injuries are so far unknown in the Mississippi Valley, the blighted 
appearance of the elms on the Department grounds in midsummer, and 
especially of the European varieties, at once attracted our attention 
when we first came to Washington, and a series of experiments was be- 
gun with a view of checking the ravages of the insect. The excellent 
opportunites thus offered for experiment and study have since been im- 
proved, and, with some prefatory passages in relation to the history 
and habits of the beetle, we will give the practical results reached. 
AN IMPORTATION FROM EUROPE. 
This beetle has done great mischief in the Old World, especially in 
Germany and France, and it is very important that the public know 
the best method of coping with it here. According to Glover, it was. 
imported as early as 1837. Its distribution was formerly confined to 
limited areas near the coast, and its earlier attacks were notably about 
Baltimore and New Jersey. 
HABITS AND NATURAL HISTORY. 
The general characteristics of this insect have been pretty well stud- 
ied abroad. Mr. E. Heegert has given an excellent account of its 
life-history, with a detailed description of the larva and figures illus- 
* This is the Galeruca crategi Forst., and G. calmariensis Fabr. In Crotch’s Check- 
list it appears as Galerucella xanthomelena. 
t Seventieth contribution to the natural history of insects. Sitzungsberichte der 
kais. Ac. Wiss., Wien, 1858, vol. 29. 
8 
