33 2 
Journal of Agricultural Research 
Vol. VII, No. 7 
Fifth instar (adult) (PI. 20, C).—Morphological characters. Antennae as follows: 
Segment I, 0.08 mm.; II, 0.064 mm.; Ill, 0.56 to 0.72 mm., average, 0.676 mm.; IV, 
0.368 to 0.464 mm., average, 0.419 mm.; V, 0.240 to 0.32 mm., average, 0.272 mm.; 
VI, (0.112 plus 0.504 mm.) to (0.128 plus 0.68 mm.), average (0.116 plus 0.582 mm.). 
Segments I and II strongly imbricated on their inner margins and armed with a few 
short spines. Segment III imbricated and armed with 53 to 60 oval, double rimmed, 
protruding sensoria which give the segment a knotted appearance. These are dis¬ 
tributed over the entire segment; and a number of short spinelike hairs are also 
present. Segment IV similar to segment III but with from 22 to 29 sensoria. Seg¬ 
ment V also similar, but the smaller number of sensoria (4 to 10) causing the imbrica¬ 
tions to appear more distinct. The distal sensorium on this segment is the usual 
fringed one and not similar to the others on the segment. Segment VI strongly 
imbricated throughout and with the usual sensory group at the base of the unguis. 
Antennae placed on small frontal tubercles which are notched within and armed 
with a few capitate hairs; vertex almost straight in some specimens, while the median 
ocellus protrudes in others; crown with a pair of tubercles placed between the com¬ 
pound eyes. This character is, however, not a constant one, as the writers have 
many specimens in which these tubercles are lacking. Prothorax with a prominent 
lateral tubercle on each side. In some specimens there are two of these tubercles 
on one side, and in the writers* specimens this seems always to be the left side. Fore¬ 
wing 2.48 mm. long and 1.008 mm. wide at its broadest part. Venation usually 
normal, first branch of media slightly nearer its insertion than it is to the tip, radial 
sector considerably curved, stigma 0.56 mm. long on the costal margin; hind wing 
1.6 mm. long, hamuli 0.56 mm. from the distal extremity. Abdomen with distinct 
lateral tubercles and with prominent dorsal tubercles on the two caudal segments; 
cauda short, conical, setose, and armed with usually three pairs of long curved spine¬ 
like hairs; anal plate bluntly conical or rounded, densely setose, and armed with many 
curved spinelike hairs. Cornicles cylindric, slightly curved, faintly imbricated and 
distinctly flanged; length 0.288 to 0.384 mm.; legs slender, hind tibiae 1.07 to 1.1 
mm.; hind tarsus about 0.096 mm. long. 
Color characters: General color brownish green, marked with black as follows: Head 
above uniform black, the prothorax and the thoracic shield black, the margins, how¬ 
ever, near the wing insertions without black markings. Abdomen with a large black 
quadrate patch on middle of dorsum surrounded by a narrow unmarked area; cephalad 
of this patch there are often a number of small transverse markings, and caudad of it a 
semicircular black marking which includes the insertions of the cornicles; this is 
sometimes fused with the quadrate patch; margins of the abdomen with three large 
rounded black spots cephalad of the insertion of the cornicles and with sometimes a few 
smaller markings, lateral margins of the thorax with a large black spot. Below marked 
with black as follows: Vertex, trophic tubercle, and margins and tip of labium; 
a small spot on the prothorax; sternal plate; a band between and encircling the 
hind coxse; cauda an d anal and genital plates. Antennae black; coxae black, trochanter 
and proximal extremity of femur black; remainder of femur, the distal extremity 
of the tibia, the tarsus, and claws black; remainder of tibia yellowish brown; cornicles 
black. Wings clear, veins thin, stigma dusky. 
Location: Found in the curled leaves of the apple and on the leaves and stems of 
the plantain reproducing. 
LENGTH of nymphal life 
The winged form requires about two days more than the wingless one 
for its immature stages, though this period may vary in exceptional cases 
from 1 to 3 days. Thus, the total length of the period is from 11 to 13 
days, the usual length being 12. The two extra days are spent in the 
fourth or pupal stage, the pupae being from 2 to 3 days old when the 
wingless form becomes adult. 
