BIOLOGY OF THE LOTUS BORER. : 9 
above the water. No data are available as to the length of life of 
the moths in the open. A series of reared moths retained alive in tin 
boxes supplied with a wad of wet cotton furnished the data on this 
point contained in Table I. 
* TABLE I.—Length of life of reared moths in confinement (in terms of days). 
‘ 
| j 
| apo ae Number 
| Maxi- |} Mini- | 
Sex. : | Average. | of moths 
| mum. | mum. | =) averaged. 
} | | 
INGE S Be Se ee he A Re Co, Sey: See SO ce eo eee Pe a A te ceeten | 14 | 2 6.77 27 
EGWEDIS- soles ce Ssee steel edhe ge OF ta eee earns Pu eae As ae er, #3 on (ePAa | 43 
THE EGG. 
The act of oviposition has not been observed, but very probably 
occurs toward dusk or at night. Nothing was known about the 
egg until Welch (14, p. 214) observed and rather incompletely de- 
scribed it. The authors have found numbers of the masses (PI. 
II, D) at various times, and as their observations differ in some 
points from those of Welch a description in somewhat greater 
detail is included. 
The egg: Thin, flat, elliptical in outline, 0.98 millimeter long, 0.56 millimeter 
wide, chorion finely reticulated with narrow elevated lines and in addition finely 
longitudinally wrinkled, dingy yellow or amber color when laid, soon develop- 
ing a narrow darker border and a paler opaque central area. They are laid 
in thick circular masses of 40 to 80 eggs, 2.5 to 3 millimeters in diameter and 
0.47 millimeter thick, each egg overlapping its predecessor shingle-fashion, about 
three-fourths covering it and lying at an angle of approximately 45° with 
the leaf surface, the mass being dingy yellow in general color. The larva 
leaves the egg through a transverse slit in the exposed end. After hatching 
the mass is dirty gray in color, somewhat shining, and much flatter than be- 
fore. It is then very loosely attached to the leaf and easily removed by a 
slight touch. 
The writers failed to note any matrix such as Welch describes. 
They did, however, note the frequent absence of the empty egg mass 
on leaves bearing very small larvae, but attributed the fact to the ease 
with which the empty egg mass is washed or blown from the leaf. 
A number of the egg masses were found, both unhatched and empty, 
and one in which the eggs were parasitized. They seem to be placed 
at any point on the upper surface of the leaf and when present on an 
~ unblemished leaf are easily seen. 
It has, of course, been impossible to determine how many eggs are 
normally laid by a female in the open. The possibilities are indi- 
cated, however, by results obtained from reared moths confined in tin 
boxes and supplied with moisture. Of 43 females so confined only 
15 oviposited. The number of eggs produced by an individual varied 
from 9 to 504, with an average for the 15 of 143 eggs. These moths 
