60 
THE SPRING GRAIN-APHIS OR " GREEN BUG." 
The following is the description of the adult, summer forms, as 
given by Mr. Pergande : 1 
Apterous female [fig. 8]. — Length 1-1.8 mm.: color yellowish green and slightly prui- 
nose, the median line darker green, the head and prothorax somewhat paler than the 
rest of the body. Eyes black. Antennae black, the two basal joints and more or less 
of the third joint at base yellowish. Legs yellowish, the tibiae brownish toward the 
apex, tarsi black. Tail dusky. The general color of the larvae and pupae is like that 
of the apterous female. Wing pads of pupa dusky to black. Antennae slender and 
about one-half the length of the body. Nectaries slightly tapering, reaching to or 
slightly beyond the end of the body. Tail slender, somewhat constricted about the 
middle, and about two-thirds the length of the nectaries. There is a distinct fleshy 
tubercle each side of the prothorax and similar tubercles along both sides of the abdo- 
men. 
Migratory female [fig. 7]. — Ex- 
panse of wings 5-7 mm.; length 
of body 1.5-2 mm. General 
coloration of the abdomen as 
in the apterous forms; head 
brownish yellow; the eyes 
brown; antennae, thoracic 
lobes, the posterior margin of 
the scutellum, and the sternal 
plate black; the two basal 
joints of the antennae yellowish 
green; legs yellow, the femora 
more or less dusky, the posterior 
pair darkest; apex of tibiae and 
the tarsi black; nectaries and 
tail yellowish, the latter chang- 
ing gradually to dusky or 
black toward the end; wings 
transparent; costa and subcosta 
yellow; the stigma somewhat 
paler, its inner edge and the 
veins black. Third discoidal 
vein with but one fork. An- 
tennae long and slender, reach- 
ing nearly to the end of the 
7 sensoria. Nectaries, tail, and lateral 
Fig. 14.— The spring grain-aphis: Pupa of winged viviparous 
female. Enlarged; actual size, 1.875 mm. (Original.) 
body, the third joint provided with 3 to 
tubercles, as in the apterous females. 
Besides the sensoria on the third segment of the antennae mentioned 
in the above description, there are from 1 to 2 on the fourth, 1 near 
the apex of fifth, and several, more or less distinct, on the base of the 
sixth. 
Measurements of antennal joints (average from 8 specimens): I, 0.082 mm.; II, 
0.059 mm.; Ill, 0.300 mm.; IV, 0.223 mm.; V, 0.215 mm.; VI, base, 0.110 mm.; 
VI, filament, 0.395 mm.; total length, 1.384 mm. 
To this description we add : 
Wingless female (fig. 8). — Coloration for this stage varying from a very pale green 
with a slight tinge of yellow to a deep apple-green. The dorsal stripe is not always 
i Bulletin 38, Div. Ent., U. S. Dept. Agr., p. 18, 1902. 
