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 111, 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 Urticacea', 

 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. 



(i) Grapta interrogationis, Fabricius, Plate I, Fig. 3, $, , 

 tinder side; form fabricii, Edwards, Plate XIX, Fig. 1,6; form 

 umbrosa, Lintner, Plate XIX, Fig. 2, ? ; Plate 111, Fig. 2}, 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). 



Biitterjfy. — 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 timbrosa, 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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