ORCHARD INJURY BY HICKORY TIGER-MOTH. 5 



PUPA. 



(PI. Ill, fig. 2.) 



Length, 10 to 13 mm; width of thorax, 6 mm; width of abdomen, 7.5 mm. 

 The abdomen is much stouter than the thorax and there is a slight constriction 

 between them; the wingpnds extend to the fifth abdominal segment; on the 

 caudal end is a transverse row of spines recurved at the end. Color when 

 newly transformed, yellowish, but soon becoming reddish brown ; margins of 

 segments and spiracles darker. 



IMAGO. 



(PI. Ill, fig. 1.) 



The following is Harris's original description of the moth (1) : 



* * * very light ochre-yellow in color ; the fore-wings are long, rather nar- 

 row, and almost pointed, are thickly and finely sprinkled with little brown dots, 

 and have two oblique brownish streaks passing backwards from the front edge, 

 with three rows of white semitransparent spots parallel to the outer hind 

 margin ; the hind-wings are very thin, semitransparent, and without spots ; and 

 the shoulder covers are edged within with light brown. They expand from 

 one inch and seven-eighths to two inches and a quarter or more. The wings 

 are roofed when at rest, the antenna? are long, with a double narrow, feathery 

 edging, in the males and a double row of short, slender teeth on the under-side, 

 in the females; the feelers are longer than in the other Arctians, and not at all 

 hairy; and the tongue is short but spirally curled. 



FOOD PLANTS. 



The hickory tiger-moth is usually recorded as a general feeder on 

 the foliage of deciduous trees and shrubs. No less than 49 host 

 plants from wklely separated families have been listed by various 

 observers. However, this wide range of food plants is confined to 

 the nearly mature larva. The number of food plants upon which 

 larvae can develop from egg to pupa is much smaller and, as far as 

 the writer has observed, is restricted to trees of the walnut and 

 hickory family and to pomaceous fruits. 



The writer has reared larvrc from egg to pupa on Japanese walnut, 

 English walnut, black walnut, apple, and pear. In the field, colonies 

 have been found frequently on all of the above and also on butter- 

 nut, quince, and once on white hickory. In spite of its name walnut 

 and not hickory seems to be its favorite food plant. An egg mass 

 was found on a sour-cherry leaf, but a colony of larvae were never 

 found feeding on cherry in the field. Miss Soule (8) records finding 

 an egg mass on a thorn leaf (Crataegus sp.). 



The lots of larvae which were fed on black walnut, Japanese walnut, 

 English walnut, pear, and apple all reached the pupa stage and 

 appeared normal. In the early larva instars the development was 

 about the same. The later instars on Japanese walnut developed 



