THE BROAD-BEAST WEEVIL. 
13 
test, beans were taken from pots 20 days after planting, and a live 
adult found in one of its burrows in a bean that had germinated. 
When disturbed, the weevils have the habit of folding their legs 
tightly and feigning death. On the plant they will fall to the 
ground, but quickly become active. In the sack or on a table they 
are apt to remain quiet, "playing possum" for some time, and it takes 
quite a prod with a pencil or pin to make them become active. 
GERMINATION TESTS OF INFESTED BEANS. 
A number of tests were made to determine the effect of weevil in- 
festation on the germinating power of the beans and at the same 
time compare new seed and that held over a year. 
Table X. — Germination tests of infested and noninfested beans; new and 
year-old seeds. 
New crop seed, percentage of 
germination — 
Date. 
Old crop seed, percentage of 
germination — 
Date. 
With 
no 
wee- 
vil. 
With 
1 
wee- 
vil. 
With 
2 
wee- 
vils. 
With 
3 
wee- 
vils. 
With 
4 and 
5 wee- 
vils. 
With 
no 
wee- 
vil. 
With 
1 
wee- 
vil. 
With 
2 
wee- 
vils. 
With 
3 
wee- 
vils. 
With 
4 and 
5 wee- 
vils. 
Apr. 26. 1916 
Nov. 20, 1916 
Dec. 1,1916 
Dec. 13. 1916 
98 
98 
96 
86 
100 
92 
98 
98 
90 
92 
94 
60 
100 
88 
68 
90 
60 
68 
86 
54 
92 
88 
26 
88 
72 
98 
88 
50 
92 
73 
28 
68 
""87" 
"""52 
70 
Oct. 27, 1916 
Nov. 20, 1916...... 
Dec. 1,1916 
Dec. 13. 1916 
Mar. 22, 1918 
Oct. 17, 1918 
96 
100 
90 
88 
84 
100 
94 
90 
70 
64 
72 
38 
86 
90 
90 
56 
80 
54 
88 
90 
90 
75 
May 8, 1916 
Mar. 22, 1918 
Oct. 17, 1918 
Apr. 28, 1916 
24 
8 
44 
Average 
95.7 
82.7 
72.7 
71.1 
69.6 
93 
71.1 
76 
60 
59 
Average of infested 1 
)eans 
74 
Average of infested 
beans 
66 
This table shows that as the number of insects per bean increases, 
the percentage of germination decreases. The drop is about 20 per 
cent from perfect beans to those infested with one weevil, and some- 
what less for each weevil up to the maximum of 4 and 5 weevils, 
which gives a germination of 60 or 70 per cent. The table also 
shows that the percentage of germination is a little more with new 
crop seeds than. with those held over for a year. 
The table, however, does not show the reason for the low germina- 
tion in the infested beans. In only a few cases does the insect actu- 
ally injure the embryo or germ, but by far the greatest damage comes 
from the fact that the holes made by the insects allow bacteria or 
fungi to enter, which cause the beans to rot. In a number of cases 
rotting takes place soon enough to prevent germination entirely, 
but a large number of beans are killed also after the seed has actually 
germinated, and before the shoot can get out of the ground. Hotting 
of the seed is much worse during cool or cold weather, when germi- 
