20 THE ERRATIC ARMY-WORM. 
have. Instudying the road traveled by the armies of such 
worms we can usually detect where the majority of them were 
born, and find, as a very generalrule, that this is an oldstraw 
stack. It seems to have wonderful attractions for this in- 
sect, and this being the case the removal or disposal of these 
useless or unsightly objects is anexcellent method to prevent 
an undue increase of army-worms. The illustration shows 
the adult insect, a pupa in its underground cell, and a larva 
in the act of eating off the chatf from an ear of wheat. 
THE ERRATIC ARMY-WORM. 
(Noctua fennica Tausch). 
As has been stated betore, almost any species of cut- 
worm, favored by exceptionally good conditions, may be- 
come a veritable army-worm. Early last spring reports. 
reached this office that the country about Hinkley was in- 
vaded by immense numbers of caterpillars which devoured 
every green thing upon the face of the ground. At the invi- 
tation of a gentleman from that place, and also prompted 
by curiosity to see this new army-worm, the entomologist. 
paid a visit to the invaded region and studied the worms. 
The great majority of these caterpillars which are shown in 
fig. 12 on plate III, had already disappeared and only com- 
paratively few were still found running about in search of 
food (fig. 13, plate IV). The'caterpillars are velvety black with 
a number of longitudinal yellowish lines and havea brownish. 
head. The presence of these worms was painfully evident. 
as they had devoured everything in the nature of a leaf, and: 
had, prompted by hunger, even eaten the young bark of such 
plants as poplars, willows, cherry, sumach and others (fig. 
14, plate IV). All the foliage of the plants that had found a. 
home in this region since the great fire in 1893 seemed to be: 
to the taste of these worms. They preferred, however, such 
plants that are bitter, hence the foliage of cherries, poplars, 
willows and sumachs was the first to be eaten; after these 
plants had been denuded nearly all others were devoured 
and only certain grasses fared better. Owing to the rainy 
spell numerous pools of water had been formed in which, 
like islands, were some young trees, but even these had been 
