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i DEPARTMENT BULLETIN 1779. 
In observations on the hatching of 8 individual nymphs, the time 
required for emergence varied from 14 to 40 minutes, the average 
being 20 minutes. The newly hatched nymph is capable of locomo- 
tion soon after completing emergence but generally remains on or 
near its parent egg cluster until the second instar is reached. All 
normal eggs in the same egg cluster generally hatch within a 24- 
hour period. 
PROPORTION OF EGGS HATCHING IN THE FIELD. 
Unless destroyed by parasites or predacious enemies, the propor- 
tion of eggs of Chlorochroa sayi hatching in the field is very high. 
Occasionally a few eggs in otherwise normal clusters were prevented 
from hatching by being deposited wrong end up. A few eggs, too, 
were deposited on top of the main egg cluster, which invariably 
prevented the lower eggs from hatching. Very few infertile egg 
clusters were collected in the field. Abnormal weather conditions 
prolonged the period‘of incubation but appeared to have no other. 
injurious effects on the eggs. 
PROPORTION OF EGGS HATCHING IN THE LABORATORY. 
In one laboratory experiment a total of 1,068 eggs were deposited 
by 30 females confined in life-history cages. Of this number a total 
of 981 eggs, or 91.88 per cent, hatched. The remaining 8.12 per cent 
were probably somewhat- affected by the abnormal cage conditions. 
NYMPHS. 
DURATION OF NYMPHAL STAGES. 
The prevailing temperature conditions have a marked influence 
in controlling the duration of the nymphal stages of Chlorochroa 
sayi in the field and in life-history cages. During the period from 
July 5 to August 18, 1916, a total of 17 nymphs were reared from egg 
to adult. (See Table II.) In this series of cages the first instar 
occupied 5 days; the second instar, from 7 to 9 days with an average 
of 8.2 days; the third instar, from 5 to 7 days with an average of 
6.4 days; the fourth instar, from 7 to 10 days with an average of 
8.2 days; and the fifth instar occupied from 13 to 17 days, the 
average being 14.9 days. From 42 to 44 days were required to com- 
plete the nymphal period, the average being 42.7 days. 
