LIBRARY

LEPIDOPTERA 473
palpi short and porrect or long and upturned; eyes smooth Dr rarely hairy.
Ocelli present. Antennre ciliate or pectinate. Tibial spurs well developed, the
middle and hind tibire sometimes spined. Wings well developed, fore wings
smoothly scaled, areole present or absent, hind wings with two anal veins, and
with frenulum and the retinaculum of the male usually elongated. The eggs
may be pale, globular. or somewhat flattened, sculptured and laid in large
masses on the host plants. The caterpillars are large, tuberculate, and covered
with dense tufted hairs frequently reddish-brown and black, The pro legs have
two incomplete circlets of hooklets. The caterpiIlars curl into a compact mass
when disturbed and are called woolly bears or hedgehog caterpillars. In some
species the full-grown larvre hibernate. Cocoons are spun of silk into which are
incorporated the shedding body hairs. The adults are largely nocturnal but
an' frequently found resting on plants during the day.
Among the many important and interesting genera and species are Arctia
Schrank: the great tiger moth, A. caja (Linn.), is a remarkable north circum-
FIG.151. The acrrea moth, Estigmene aCTlea (Drury), a
common North American species. (From [nseets oj West6rn
Ntn'th America.)
polar species which has no less than six color phases in the higher mountains
and northern parts of North America.
Apantesis Walker; a group of striking-colored moths usually dark with linear
white, yellow, or red patterns on the fore wings and black-margined and spotted
yellow, orange, or red hind wings. The commonest North American species is
A. virgo (Linn.), the larVa! of which feed upon many succulent weeds and truck
crops.
Diacrisia Hubner (Spilosoma Stephens): the commonest European species
is D. fJUlpinaria (Linn.) and of North America the Virginia tiger moth, D, virginica
(Fab.). The caterpillars are omnivorous on a wide variety of plants.
Estigmene Hubner includes the well-known salt marsh caterpillar, E. acr;;ea
(Drury), of North America, which is a pest of many agricultural crops.