The Moths and Butterflies 
404 
dagger-moth Acronycta (Figs. 586 and 587), so called from the rather uncer¬ 
tain small black dagger-like markings of the fore wings, have the larva in 
some species covered with long colored stiff hairs; the familiar caterpillar 
of A. americana is densely clothed with 
yellow hairs, besides bearing a pair of 
long black pencils on the first abdominal 
segment, another pair on the third, and 
a single pencil on the eighth. It feeds on 
the leaves of elm, maple, and other trees, 
and when at rest curls sidewise on a leaf. 
The army-worm (Fig. 583), a black, 
yellow, and green striped caterpillar 
that occurs over nearly all the country 
and often appears in enormous numbers, 
causing great losses to grain-fields, is. 
the larva of a dull-brown moth, Leu- 
a 
Fig. 584. — Venation of a Noctuid, 
Agrotis ypsilon. cs, costal vein; sc, 
subcostal vein; r, radial vein; m, 
medial vein; c, cubital vein; a, anal 
veins. (After Comstock; enlarged.) 
cania unipuncta , marked in the center 
of each fore wing with a distinct white 
spot. Perhaps as severe a sufferer as 
any other field product from the attacks 
of Noctuid larvae is cotton. The cotton- 
worm, Aletia argillacea , feeds on the foliage of the cotton-plants and the cotton 
boll-worm, Heliothis armigera , attacks the cotton pods or bolls. These two 
caterpillars cause losses to the cotton-growing states of millions of dollars. 
Fig. 585. Fig. 586. 
Fig. 585. —Larvae of the gray dagger-moth, Acronycta occidentalis. (After Lugger;, 
natural size.) 
Fig. 586. —Gray dagger-moth, Acronycta occidentalis. (After Lugger; natural size.) 
every year. The cotton boll-worm is more or less familiar in states farther 
north, under the name of corn-worm, where it is found feeding on ears of 
green corn and on tomatoes. It is a naked, greenish-brown, dark-striped 
caterpillar. The moth has pale clay-yellow fore wings with a greenish tint, 
the hind wings paler. 
Among the most conspicuous of all the caterpillars are the not unfamiliar 
larvae of the tussock-moths, Lymantriidse, one common species infesting our 
