Genus Grapta 
ing upward from the base. The summit is broad and flat. The 
sides are marked by a few equidistant narrow longitudinal ribs, 
which increase in height to the top. A few delicate cross-lines 
are interwoven between these ribs. They are laid in clusters or 
in short string-like series (see p. 5, Fig. 10). 
Caterpillar. —The head is somewhat quadrate in outline, the 
body cylindrical, adorned with rows of branching spines (see 
Plate III, Figs. 23, 27, 31-33, 38). 
Chrysalis. —The chrysalids have the head more or less bifid. 
There is a prominent thoracic tubercle, and a double row of 
dorsal tubercles on the abdomen. Viewed from the back they 
are more or less excavated on the sides of the thorax. In color 
they are generally some shade of wood-brown or greenish. 
The caterpillars feed for the most part upon the Urticacece , 
plants of the nettle tribe, such as the stinging-nettle, the elm, 
and the hop-vine, though the azalea and wild currants furnish 
the food of some species. 
The genus is confined mainly to the north temperate zone. 
(1) Grapta interrogationis, Fabricius, Plate I, Fig. 3, $, 
under side; form fabricii, Edwards, Plate XIX, Fig. 1, $ ; form 
umbrosa, Lintner, Plate XIX, Fig. 2, $ ; Plate III, Fig. 23, larva, 
from a blown specimen; Fig. 27, larva, copied from a drawing 
by Abbot; Plate IV, Figs. 21, 22, 24-26, 40, chrysalis (The Ques¬ 
tion-sign). 
Butterfly. —Easily distinguished by its large size, being the 
largest species of the genus in our fauna. The fore wings are 
decidedly falcate, or sickle-shaped, bright fulvous on the upper 
side, spotted and bordered with dark brown and edged with pale 
blue. On the under side they are mottled brown, shaded with 
pale purplish, and have a silvery mark shaped like a semicolon 
on the hind wings. The dimorphic variety umbrosa, Lintner, has 
the upper side of the hind wings almost entirely black, except 
at the base. Expanse, 2.50 inches. 
Early Stages. —These have been frequently described, and the 
reader who wishes to know all about the minute details of the 
life-history will do well to consult the pages of Edwards and 
Scudder, who have written voluminously upon the subject. The 
food-plants are the elm, the hop-vine, and various species of nettles. 
This is one of our commonest butterflies. It is double- 
brooded in the Middle States. It hibernates in the imago form, 
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