31 
doing great damage by gnawing around the stems and causing the 
bunches of grapes to fall. 
Of fruit trees, attack to the foliage of peach, apple, and orange is 
recorded, and egg masses have been taken on the leaves of lemon, 
hickory, and s}^camore. Riley has stated that even spruces are subject 
to attack. Of its occurrence on fruit trees, Hubbard (in speaking 
of its feeding on the orange) says that "although the young cater- 
pillars eat the leaves to some extent, they soon find their way to some 
other and more succulent food plant.' 1 It is obvious, therefore, that 
the feeding of the fall army worm on the foliage of trees is quite 
exceptional, and due usually to the fact of the eggs having been 
deposited on the leaves of the trees, since mature larvae are scarcely 
if ever seen on trees. There is a possibility that the maturing larvae 
may attack the leaves of the trees when driven to it through scarcity 
of other food, but this is doubtful, since these larvae prefer low-growing 
plants. 
It would seem probable that it might be a matter of common occur- 
rence for the species to invade greenhouses when unusually abundant 
on grasses and other vegetation in the vicinity, but our records show 
onl}^ injuries to violets among hothouse plants. 
Instances of extreme foods are to be found when stacks of fodder 
are attacked, as instanced by Glover (5), previously mentioned. 
It is not alone the leaves of plants that are injured, as was known in 
Smith and Abbot's day upward of a century ago. The caterpillars 
delight in eating into the hearts of their food plants, cutting into the 
still folded leaves of corn and even boring into the ears after the man- 
ner of the boll worm or corn-ear worm (Ileliothis armiger)^ devouring 
alike husk, silk, and unripe seeds. 
OBSERVATIONS ON THE LIFE HISTORY. 
The life history of the fall army worm, as previously intimated, has 
not } T et been studied as carefully in any single localit} T as its impor- 
tance as a pest deserves. Even the stage or stages in which the insect 
passes the winter were in doubt until 1900. 
HIBERNATION.. 
That it did not hibernate in the egg condition in the latitude of the 
District of Columbia was proved by the writer in 1899. During Sep- 
tember of that 3^ear we had under observation great numbers of egg 
masses on grasses and on the walls of buildings in the vicinity of grass, 
and every mass hatched. A lot which was kept in our insectory under 
1 Like the boll worm and some species of cutworms, the fall army worm is inclined 
to be carnivorous at times, and even cannibalistic, devouring larvae smaller than 
itself, and thus attacking its own species. 
