LEPIDOPTERA. 
321 
The Salt-marsh Caterpillar, Estigmene acraa (Es-tig-me'ne 
a-crde'a).—The popular name of this insect was given to it 
by Harris, and was suggested by the fact that the salt- 
marsh meadows about Boston were overrun and laid waste 
in his time by swarms of the larvae. But the name is mis¬ 
leading, as the species is widely distributed throughout the 
United States. The moth 
(Fig- 393) i s white, marked 
with yellow and black. 
There are many black dots 
on the wings, a row of 
black spots on the back of 
the abdomen, another row 
on the venter, and two rows on each side. The sexes differ 
greatly in the ground-color of the wings; in the female, this 
is white throughout; in the male, only the upper surface of 
the fore wings is white, the lower surface of the fore wings 
and the hind wings above and below being yellow. The num¬ 
ber and size of the black spots on the wings vary greatly. 
There are usually more submarginal spots on the hind 
wings than lepresented in our figure. 
The Fall Web-worm, Hyphantria ciinea (Hy-phan'tri-a 
cu'ne-a).—A very common sight in autumn in all parts of 
our country is large ugly webs enclosing branches of fruit or 
forest trees. These webs are especially common on apple 
and on ash. Each web is the residence of a colony of 
larvse which have hatched from a cluster of eggs, laid on a 
leaf by a snow-white moth. There is a variety of this 
moth in which the fore wings are thickly studded with dark 
brown spots. Every gradation exists between this form 
and those that are spotless. The species winters in the 
pupa state,-and the moths emerge during May or June. 
The webs made by this insect should not be confounded 
with those made by the Apple-tree Tent-caterpillar. The 
webs of the Fall Web-worm are made in the autumn, and 
Fig. 393 *—Estigmene acrtea. 
22 
