131 
immediate vicinity of the empty egg-shells, soon attaching them¬ 
selves, and there they remain (Fig. 47) until adult. During the 
immature stages the individual molts four times, becoming adult 
at the last molt. The entire life period of the insect, from the 
time the egg is deposited until the adult emerges, is a month to 
five and a half weeks at the ordinary greenhouse temperature in 
summer. 
Fig. 47. White Fly, Aleyrodes vaporanorum, nymphs 
on leaf. Twice natural size. (Connecticut Experi¬ 
ment Station.) 
The presence of the white fly is easily detected, owing to its 
conspicuous white wings. When infested plants are disturbed the 
insects take flight, and if numerous arise in clouds. Plants are 
often so badly infested that they wilt down during the warmer 
parts of the day, and finally succumb owing to the loss of sap. 
Fig. 48. White Fly, Aleyrodes vaporartorum, adults 
on leaf. Twice natural size. (Connecticut Experi¬ 
ment Station.) 
