76 WHITE FLIES INJURIOUS TO CITRUS IN FLORIDA. 
TaBLe XIV. —Activity of the citrus white fly in oviposition during different parts of the day. 

Mean tem-} Number | Per cent of 
Time of day. perature of eggs total eggs 
for period. | deposited. | deposited. 


Sei 
6 a. m.-8'a.Mm.... 82 20 2.6 
8 a.m.-10.4. Mm... 89 55 13 
10 a.m.-12m..... 91 35 4.7 
12m.-2p.m...-. 92 65 8.7 
2p.m.-4p.m...- 90 30 4 
4p.m.-6 p.m.... 85 197 26. 1 
6p.m.-8 p. m....| 81 248 32.9 
8 p.m.-—6 a.m.... 74 103 13. 7 
6 a.m.-6. a.m... 181.6 753 100 



1 Average temperature for entire Cay of 24 hours; not the average of the 8 periods. 
From the data it will be seen that while oviposition occurs at all 
times of the day, nearly 60 per cent of the eggs are deposited between 
4 p.m. and 8 p. m., and that oviposition does not cease on the ap- 
proach of darkness. The variation in the number of eggs deposited 
during the periods from 6 a. m. to 4 p. m. has little significance. It 
was noted that the least number of eggs were deposited when the 
bright sun fell directly upon the cage. 
In further evidence of the greater activity of oviposition during 
the latter part of the day, two other cages were started on August 1, 
1909. One cage placed repeatedly over the tenderest growth resulted 
in 698 eggs being laid between 10.15 a. m. and 4.15 p. m., as com- 
pared with 895 eggs laid between 4.30 p. m. and 7.30 p.m. The 
second cage, covering spring growth, gave 115 as compared with 786 
eggs deposited during the same periods. 
Relation between oviposition and food supply.—As the egg-laying 
‘capacity of a single female is close to 250 eggs and but 25 well- 
developed eggs have ever been seen in her abdomen at any one time, 
it is necessary that she obtain nourishment sufficient to mature her 
numerous ‘‘potential” eggs. There remain many interesting obser- 
vations and experiments to be made on the relation between oviposi- 
tion and food supply. That females deposit fewer eggs when feeding 
upon many of the recognized food plants other than citrus than they 
do on the latter is a subject of considerable interest. While adults 
feed apparently as contentedly upon new growth of China trees and 
umbrella China trees, they do not appear to deposit as many eggs 
per female on these host plants as on citrus. The extremely small 
number of eggs laid by females swarming over new growth of wild 
persimmon in June at Orlando is even more astonishing considering 
the marked preference shown by the females for this growth over the 
spring growth of orange. Even on citrus itself oviposition is influ- 
enced by the ages and corresponding toughness of the leaves, though 
not as markedly as is that of the cloudy-winged white fly. In one 
instance equal numbers of adults were confined on a tender and an 
