THE CITRUS WHITE FLY: LIFE HISTORY AND HABITS. 73 
of the tender growth, are favorite places for oviposition, and not 
infrequently as high as 40 per cent of the eggs are there laid, even 
when the adults. are not very abundant. Although eggs may be 
deposited along the leaf margin, it is seldom that they are laid on the 
margin itself, as is the case with the cloudy-winged white fly. Even 
when not crowded for leaf space, the adults sometimes settle upon the 
under side of young fruit, where they deposit eggs freely and appar- 
ently feed. 
DAILY RATE OF OVIPOSITION. 
Previous to these investigations no data have been published on 
the daily rate of oviposition. In obtaining the data given in Table — 
XII, the females recorded were collected at random throughout the 
grove, without regard to age, and, together with males not mentioned, 
were caged over leaves cleaned of all eggs and larve of the white 
fly and allowed to remain the recorded time, when the adults were 
removed and the eggs counted. 
TasLeE XII.—Daily rate of oviposition of the citrus white fly. 











ear avemee 
; “Sab umber | number | Average 
Record | Dateldeposited pepe Pe een ofeggs jofeggsper| mean 
No. e(ehey: : Fomrtales Teese depos- female | tempera- 
asaept RYDE ited. per 24 ture. 
hours. |° 
| Hours. oR 
1 Feb. 23-24, 1909. ....-- 14 26 197 13 74.5 
2 Apr WA —T5 1907s =~ 2. -| 3 103 98 7.6 68. 2 
3 Apr. 20-21, 1909....... | 50 | 24 454 9.1 77. 2 
4 Apr. 21-22, 1909... ....- 40 24 405 10. 1 78. 2 
5 | June 16-17, 1909._..... 30 | 24 360 12 82 
6 | July 17-18, 1907. .-._-| 255 21 2, 533 11.3 $2 
Zi July 22-23, 1907....... 105 24 1,216 11.6 85 
8 | July 24-26, 1907-.....- 50 46 1,331 13.8 84 
9 | Aug. 17-18, 1907....... | 70 24 805 11.5 81 
10 | Sept. 21-22, 1908.......| 35 24 | 405 11.6 79 
| | 

Number eggs per day per female, grand average, 11.2. 
The generally uniform results obtained in the nine records when 
the average mean temperature was about 75° F. or above, together 
with the grand average daily rate of oviposition for individual 
females whose age was definitely known, as shown in Table XIII, 
indicate that each female normally deposits on an average 10 or 11 
eggs a day. Varying degrees of temperature above a daily mean 
of 75° F. do not correspondingly increase the number of eggs 
deposited. However, temperatures below an average mean of 72° F. 
(estimated) have a distinct checking effect upon oviposition, as shown 
by record No. 2. . 
Notwithstanding the general average number of eggs per day 
deposited by the females of all ages in Table XIJ, and the same for 
the females of known ages for the total number of days they lived, 
in Table XIII, reference to the daily oviposition records in the latter 
