1022 I. M. Hawtey 
which varied from circular depressed areas, each with a dark spot in the 
center, to ragged holes, with the bean coat badly ruptured (Plate LX XI, 
2, and fig. 100, B). The term dimples has been applied to these scars. 
Since these markings bear a strong resemblance to hemipterous punctures 
on other plants, specimens of the dusky plant bug, Adelphocorus rapidus 
‘fig. 101), one of the commonest mirids in western New York bean fields, 
were caged over a potted bean plant 
on August 15, 1918. When examined 
on September 4, the pods on this 
i plant were misshapen and covered 
with dark, raised, wart-like areas 
(fig. 100, A). The seed in these pods 
showed evidence of dimpling. 
In the summer of 1919 an effort 
was made to verify this observation 
and to find other insects that might 
have a share in the work. On August 
11 a cage containing A. rapidus was 
placed over two bean plants, the pods 
of which were still green. When these 
were examined on August 28, most of 
the beans were dimpled. One hun- 
dred pods picked near the cage con- 
tained only one dimpled seed. 
The feeding of A. rapidus fre- 
quently produces such ragged, dis- 
colored marks on the bean seed that 
it would seem that the imsect, in 
addition to removing juices from the 
bean, possibly secretes a toxin that 
s ff acts on the bean tissues. The nature 
S 4 of the puncture appears to be influ- 
enced by the stage of development 
Fic. 101. THE DUSKY PLANT BUG, ADEL- of the pod at theitime of thepattacke 
PHOCORUS RAPIDUS : 
The seed is stunted when punctured, 
Heer eu teey OF tne ace “and the subsequent growil aboutthe 
injured part produces the dimple. 
Beans the pods of which are still green tho nearly mature, tend to suffer 
the most. In addition to feeding on the pods, the insect attacks also the 
blossoms, the leaves, and the stalks, but on these no serious deformation 
seems to result. 
It is not always easy to distinguish, by their outward appearance, the 
pods that contain dimpled beans. The pods may be free from the rough- 
ened brown areas and still contain injured beans. Some have been found 
