8 BULLETIN 436-, U. S. DEPARTMENT OF AGRICULTURE. 
Table I. — Combined length of egg, larval, and pupal stages of the desert corn flea-beetle 
(Chaetocnema ectypa) at Tempe, Ariz., 1915. 
Cage No. 
Date 
adults 
placed 
in cage. 
Date 
adults 
removed. 
Average 
date of 
oviposi- 
tion. 
New adults 
emerged. 
Com- 
bined 
length 
of 
stages. 
Aver- 
age 
mean 
tem- 
pera- 
ture. 
Date. 
No. 
T90 
Mar. 12 
...do.... 
...do.... 
Apr. 12 
Apr. 26 
...do.... 
May 25 
...do.... 
May 26 
...do.... 
June 21 
...do.... 
...do.... 
Mar. 19 
...do.... 
...do.... 
Apr. 19 
Apr. 30 
...do.... 
May 27 
...do.... 
May 28 
...do.... 
June 24 
...do.... 
...do.... 
Mar. 16 
...do.... 
...do.... 
Apr. 16 
Apr. 28 
...do.... 
May 26 
...do.... 
May 27 
...do.... 
June 22 
...do.... 
...do.... 
May 13 
(May 6 
{May 14 
[May 20 
/May 13 
\May 20 
...do 
/June 10 
\June 30 
/June 26 
\July 3 
June 26 
f June 25 
June 26 
{June 28 
June 30 
[July 3 
/June 26 
\June 30 
/June 25 
\June 26 
[July 16 
Uuly 17 
[July 20 
f..do 
{July 21 
Uuly 23 
(Aug. 23 
{Aug. 24 
[Aug. 25 
/..do 
\Aug. 26 
2 
2 
1 
2 
3 
1 
3 
2 
2 
2 
2 
2 
3 
5 
2 
2 
4 
4 
2 
1 
3 
4 
2 
2 
2 
5 
2 
2 
6 
3 
3 
1 
Bays. 
58 
51 
59 
65 
58 
65 
34 
43 
63 
59 
66 
31 
30 
31 
33 
35 
38 
30 
34 
29 
30 
24 
25 
28 
28 
29 
31 
32 
33 
34 
34 
35 
F. 
64 
64 
64 
64f 
64 
64f 
65 
71 
74* 
73§ 
75 
79J 
79* 
79* 
79f 
80 
80| 
80 
80£ 
80 
80 
84£ 
84f 
841 
84f 
f£* 
85 
86 
86 
86 
86 
86 
T91 
T92 
T. 117 
T 136 
T137 
T 170 
T 171 
T173 
T175 
T193 
T194 
T359 
82 
37.50 
THE EGG. 
The eggs are deposited at or near the surface of the ground, either 
on the stem of the host plant just below the surface of the ground, 
and within the soil, or, as was found by Mr. Wilson, on the old shell 
of the seed from which the plant germinated. They are usually de- 
posited singly, but six or more may be placed at one location and at 
the same time. It was very difficult to make observations upon the 
natural place of oviposition under normal conditions because of the 
minuteness of the eggs and the consequent inability to see them unless 
the ground in which they were placed was very dark in color. In 
confinement beetles deposited eggs quite readily through cheesecloth 
upon any object which might be underneath, providing the surface 
of the object was kept moist. This fact was made use of in securing 
eggs, and cages (PL I, figs. 1, 2) were constructed with cheesecloth 
bottoms, having moist, dark-colored blotting paper beneath the 
cloth. The eggs, being deposited on the dark blotting paper, were 
easily counted and transferred to cages for records on the period of 
incubation. 
