10 BULLETIN 1238, U. S. DEPARTMENT OE AGRICULTURE 



much wider than the rest of the body, yellowish green to yellowish brown with 

 a narrow posterior margin of brown. Thoracic shield varying from much the 

 same color as the head to olive green, lighter anteriorly. Thorax and abdomen 

 yellowish green to olive green, dorsum with a median longitudinal darker stripe. 

 Between the dorsal and lateral rows of tubercles is a much narrower longi- 

 tudinal dark line. Tubercles pale, with a dark green spot in the center of each. 

 Anal segment light green. 



Ventral surface lighter green than dorsal. Legs about concolorous with the 

 ventral surface, dusky at the tips. Three pairs of prolegs: A very small pair 

 on the fifth abdominal segment, and larger ones on the sixth and anal segments. 

 Hairs very short and sparse. 



When full fed, the larvae become a lighter green with narrow longitudinal 

 pale lines, which become more distinct in the next instar. 



Second stage. — Width of head 0.61 to 0.66 millimeter, average 0.64 millimeter, 

 length when full fed about 8 millimeters. General color green, varying from 

 pale yellowish green to very dark green. Individuals from the same egg 

 cluster often show wide variations in color. Head light green with varying 

 areas of dusky green ; in very dark specimens the head becomes almost entirely 

 dark green. The middle of the dorsal surface of the body has a darker longi- 

 tudinal stripe, which usually does not extend far into the anal segment. On 

 each side of this median stripe is a pair of light, narrow, longitudinal lines ; 

 and below the spiracles, following the folds of the integument, an irregular 

 light line. Tubercles concolorous with the surrounding surface, except for a 

 dark dot in the center. Spiracles dark-margined. Ventral surface varying 

 from light to dark green with a lighter median area. 



Third stage. — Width of head 1.05 to 1.13 millimeters, average 1.09 milli- 

 meters ; length when full fed 14 to 15 millimeters. General color green, vary- 

 ing from pale to very dark, almost black. Larvre reared in battery jars in 

 the insectary averaged much darker in color than those in the same stage col- 

 lected in the field. Head varying from pale green to very dark, almost black ; 

 sometimes a mottled mixture of light and dark green. Markings similar to 

 those described in the previous instar. On each side of the median dorsal 

 stripe is a pair of light longitudinal lines, and in the dorsal area there is fre- 

 quently a faint suggestion of a third pair of lines. Below the spiracles a 

 broader irregular light line follows the folds of the integument. In some 

 individuals, especially the lighter colored ones, the pale longitudinal lines 

 become more or less partial, being broken and interrupted. Anal segment 

 sometimes mottled with a very dark green. Spiracles dark-margined. Ventral 

 surface lighter in color than the dorsal, usually with the median longitudinal 

 portion lighter still. 



Fourth stage (PI. II, A). — Width of head 1.65 to 1.93 millimeters, average 

 1.77 millimeters ; length when full fed and ready to enter the ground 20 to 27 

 millimeters. General color, as in previous instars. very variable, ranging from 

 very light green to very dark and sometimes brownish green. Head and 

 anal segment varying from a very pale to darker green, sometimes mottled 

 with black, sometimes almost entirely black. In light-colored individuals the 

 head is frequently mottled with areas of creamy white. Body markings as 

 described in previous instar, with further variations. The dorsal area fre- 

 quently has in it faint suggestions of additional light longitudinal lines. Some 

 of the lighter colored larva? have a series of irregular splotches of black behind 

 each spiracle, that on the prothorax extending in front of the spiracle : in 

 other larva? some of these dark spots are present and others missing. Some 

 light-colored individuals have darker markings dorsally on the prothorax 

 and on the seventh and eighth abdominal segments. The light longitudinal 

 lines frequently have a yellowish tinge, and in rare cases a reddish brown 

 color. Other variations doubtless occur. Spiracles margined with dark brown. 

 Ventral surface pale green, even in darker specimens, lighter in color along 

 the median line, and sometimes with a pair of faint, interrupted, light, longi- 

 tudinal lines on the outer edge. 



Broadly oval in shape, 10 to 13 millimeters in length, with particles of grit 

 and soil woven in with the silk. The cocoon is very tough, so much so that 

 it is difficult to open without injury to the larva or papa within (PI. II, F). 



Previous to pupation, the larva lies doubled within the cocoon. 



