90 
* 
The larvae are either green or yellow ; the latter being those which 
ultimately acquire wings; before changing into pupae, they usually 
acquire a pale reddish color, and are dusted over with white powder. 
The wingless females are dull blackish, tinged with ; green, and 
sprinkled with fine whitish powder ; head and generally two bands on 
the thorax, black ; the abdomen is usually marked with black spots 
along the sides ; honey-tubes rather short; antennae black, and not 
more than half as long as the body. Winged females, similar ; length 
of the body, six-hundreths of an inch ; general color, black ; the ab¬ 
domen dark greenish, with black dots along each side and three black 1 
bands at the tip. 
Mr. Walsh describes those he found infesting the roots as having 
the general color, both of the pupa and perfect insect, pale green ; 
the female pupa usually has three, short, transverse dark lines on the 
thorax, and three similar ones on the abdomen. It is figured in the 
fifth volume of the Transactions of the Illinois State Agricultural Society. 
(I. fig. 14.) The antennae are unusually short, scarcely reaching the tip of 
the thorax ; the honey-tubes are also rather short ; the first discoidal 
vein is farther from the second than the second is from the third, and 
the stigma is promineut and pointed at each end. He states that the 
pupa is dusted over with a whitish bloom like that of a plum, and 
with dusky markings. 
In the latter part of July I found an. Aphis feeding on the tassels 
of corn, which upon examination I found to belong to this species; 
late in the season other specimens were sent me in alcohol, which 
had been gathered in May in large numbers on the roots of corn. 
These, although in the pupa and larva state, showed so clearly the 
marks and other characteristics mentioned by'Mr. V\ alsh, that there 
was no mistaking their identity. 
It is therefore quite certain that this species is not confined to any 
one part of the plant, but infests the greater portion of it, at least its 
most vital parts, and when very abundant, as it is in some cases, does 
serious injury. The root variety appears to retain the pupa form for 
some time, and I think it more than probable that many of them 
never acquire complete wings, although the wing-cases are formed. 
I add here a description of the specimens found on the tassels. 
Wingless individuals. (III. fig. 14.)—The full grown are of an apple green 
color throughout except the front of the head, which is dark; honey-tubes 
short, cylindrical, not reaching quite half way to the tip of the abdo¬ 
men, deep black with small black spots surrounding the base, body el¬ 
liptical or slightly ovate in outline and of but moderate width; the 
very young have the sides nearly parallel; antennae half scarcely the 
length of the body, dark brownish 7-jointed, third joint the longest, 
about equal in length to the fourth and fifth united, fourth, fifth, and 
sixth nearly equal in length, seventh a little longer than the sixth; 
whole antennae having a few scattering hairs. A stripe running along 
the margin at each side of the abdomen of a little darker shade than 
the central portion; legs dusky, darker at the joints and tips. 
Winged individuals .—Head and thorax of a shining black; abdomen 
pale greenish-yellow, dotted along the lateral margin with black; honey 
tubes black, similar to those of the wingless individuals; legs dusky, 
pale at the immediate base; antennae about half the length of tht 
body; beak very short, scarcely reaching beyond the base of the fore 
