734 Rospert MATHESON 
The majority of this generation are wingless females; at least this 
has been the case in the writer’s rearing experiments. In the field con- 
siderable numbers of winged forms developed, about 25 per cent so far 
as the writer could judge. These undoubtedly migrated to the summer 
food plant, tho no direct observations were made in the field. In cage 
experiments the winged forms readily reproduced on plantain as well as 
on apple. 
Reproductive capacity 
The second generation begins active reproduction during the last few 
days of May and reaches its maximum about the middle of June. The 
length of the individual productive period varies from 20 to 32 days, 
the average being 25 days. As the stem mothers continue reproducing 
until the latter part of June, the productive period of the second genera- 
tion extends from the last few days of May until about the middle of 
July, the maximum reproduction occurring about the middle of June or 
slightly later. The average daily production (4.68) is lower than that 
of the stem mother, and the total production of each individual (average 
119.2) is much less. 
Description of stages 
First instar.— Length 0.8 mm.; width 0.44 mm.; cornicles 0.08 mm. long. 
'The young, when just born, are light cream-color thruout and are 
very active. The antennae and the legs are long, giving the young insect 
a sprawling appearance. The eyes are at first reddish but soon 
turn black. The distal ends of the tibiae and the tarsi become black 
shortly after the insect hatches. The entire body soon becomes covered 
with a delicate white pulverulence. The length of this instar is 2+ days. 
Second instar.— Length 1 mm.; width 0.5 mm.; cornicles 0.12 mm. long. 
The general color and markings are similar to those of the first instar; 
there is a faint tinge of red in the yellowish ground coloring, otherwise 
no difference can be observed. The length of this instar is 2+ days. 
Third instar.— Length 1.2 mm.; width 0.8 mm.; cornicles 0.2 mm. long. 
The general color is yellowish, with the sides of the abdomen around 
the bases and between the cornicles reddish; the head is somewhat dusky. 
The entire body is covered with a fine white pulverulence. The antennae 
are 6-jointed, with the basal half yellowish and the remainder black. 
