REMEDIES AND ‘PREVENTIVE MEASURES. 55 
of spots; is winged in both sexes; and the female prefers to oviposit on 
Box Elder (Negundo aceroides), the Poplars, Cottonwoods, Ashes, and 
Willows. The worm feeds, however, on many other trees, but not upon 
Conifers. It has numerous enemies and parasites. 
REMEDIES AND PREVENTIVE MEASURES. 
WINTER WORK. 
The preventive measures that can be taken during winter time vary 
according to the species to be dealt with. For No. 1, or the Gal- 
eruca, Which is confined to the Elms, no treatment of the trees them- 
selves or of the boxes; in fact, no treatment that can well be given in 
the winter season will avail much in destroying the insect in its hiber- 
nating retreats, because the parent beetle finds shelter in all sorts of 
out-of-the-way places. It flies long distances, especially upon awaken- 
ing from its winter torpor, so that it may be attracted to the trees trom 
regions into which it is practically impossible to effectually pursue and 
detect it. 
With No. 2, the Thyridopteryx, on the contrary, effective work can 
be done during the winter time or when the trees are bare. The bags 
which contain the hibernating eggs, and which are very easily detected, 
then may be gathered or pruned and burned. This work may be so 
easily done that there is no excuse for the increase of this species. 
Where intelligent action is possible the bags were better collected and 
heaped together in some open inclosure away from trees, rather than 
burned. By this means most of the parasites will in time escape, while 
the young Bag-worms, which will in time hatch and which have feeble 
traveling power, must needs perish from inability to reach proper food. 
Much can also be done with No. 3, the Orgyia, because 1t also hiber- 
nates in the egg state upon the female. cocoons upon the trunks and in 
all sorts of recesses. 
In regard to No. 4, the Hyphantria, which is the species we are more 
particularly dealing with, something also may be done in the winter 
time by systematic clearing away of the cocoons from the sheltered 
places in which they may be found. These hibernating retreats are, 
however, so numerous about our houses and our grounds, that complete 
destruction of all cocoons becomes an impossibility. 
ONE SIMPLE PREVENTIVE REMEDY FOR ALL. 
It so happens, fortunately, that there is one thoroughly simple, cheap 
and efficacious remedy applicable to all tour of these tree depredators. 
From the uatural history facts already given it is clear that they all 
begin their work very much at the same season or as soon as the leaves 
are fairly developed, and arsenical mixtures properly sprayed on the 
trees about the middle of May and repeated once or twice at intervals 
