32 BULLETIN 1428, U. S. DEPARTMENT OF AGRICULTURE 
Table S. — Long developmental period of the cadelle, etc. — Continued 
No. 
Date of 
fifth 
molt 
Length 
of fifth 
larval 
stage 
Date 
larva 
entered 
hiberna- 
tion 
Date 
pupated 
Length 
of last 
larval 
and pre- 
pupal 
stage 
Date 
adult 
emerged 
Length 
of 
pupal 
stage 
Length 
of period 
egg to 
adult 
Food of larva 
1 
2. . 
1922 
Sept. 25 
Days 
63 
1922 
Oct. 14 
Aug. 23 
Oct. 23 
Aug. 23 
Oct. 22 
Aug. 29 
Oct. 7 
Sept. 27 
Sept. 22 
Sept. 27 
Aug. 29 
Oct. 10 
Oct. 12 
Oct. 19 
Oct. 27 
Oct. 25 
—do 
Oct. 29 
Nov. 2 
Oct. 22 
1923 
May 9 
Apr. 22 
May 27 
July 12 
Apr. 6 
Mar. 20 
Apr. 8 
June 10 
May 13 
Apr. 3 
June 21 
Apr. 8 
May 8 
Apr. 27 
May 30 
June 5 
June 8 
June 21 
June 3 
June 29 
Days 
226 
262 
251 
83 
195 
215 
202 
31 
48 
192 
94 
200 
230 
220 
80 
85 
86 
20 
65 
19 
1923 
May 27 
May 16 
June 7 
July 21 
Apr. 29 
Apr. 6 
May 3 
June 23 
May 30 
Apr. 27 
July 1 
May 1 
Mav 27 
May 17 
June 10 
June 15 
June 22 
July 1 
June 15 
July 12 
Days 
18 
24 
11 
9 
23 
17 
25 
13 
17 
24 
10 
23 
19 
20 
11 
10 
14 
10 
12 
13 
Days 
387 
375 
396 
410 
327 
291 
304 
355 
331 
298 
363 
271 
297 
283 
296 
301 
308 
317 
301 
328 
Barley flour. 
3 
4 
5 _.. 
Sept. 18 
1923 
Apr. 20 
67 
256 
Broken wheat. 
Corn. 
Do. 
6 ___ 
Do. 
7 __ 
Do. 
8 
Do. 
9 
10- 
Mar. 26 
213 
Do. 
Do. 
11-- 
Do. 
12.-_ 
Do. 
13 . 
Do. 
14. 
15-_ 
16. . _ 
Do. 
17_-_ 
18- _ 
19- _ 
20- _ 
June 1 
Mar. 30 
June 10 
56" 
20 
55 
Graham flour. 
Do. 
Do. 
Do. 
SEASONAL HISTORY 
The cadelle passes the winter months in the adult or larval stage. 
The data of Tables 7 and 8 indicate that the time spent by the insect 
in its egg and pupal stages is fairly short, but great variations may 
be expected during the larval stage, which may be as short as 48 days 
or, according to McColloch (£2), as long as 1,248 days. Further- 
more, the adult itself has been known to live almost 22 months and 
may lay eggs over a period of more than one year (Table 2). Tak- 
ing these facts into consideration, together with the influence of the 
time of hatching upon length of larval life (Table 4) the reader can 
appreciate that the generations become hopelessly confused. In 
warehouses and granaries the adults overwintering have their num- 
bers greatly augmented during late spring and early summer by the 
newly emerged adults developing from the overwintering larvae. It 
therefore happens that at this season of the year the adults are espe- 
cially abundant in climates having a cold winter. The overAvinter- 
ing adults begin ovipositing early in the spring (often as early as 
February in warm buildings) and continue oviposition throughout 
the summer. Eggs laid during early spring hatch and develop 
through to adults by the end of June or early July. These midsum- 
mer adults lay eggs the larva? from which usually winter over in all 
degrees of maturity; many become full grown by fall, and a few 
transform to the adult at that time. The larvae that winter over 
transform in the spring and the emerging beetles lay eggs all through 
the summer and hibernate during the following winter. In sub- 
tropical and tropical climates it seems probable that development is 
more or less continuous and that there is much overlapping of 
generations. 
