KEENEL-SPOT OF THE PECAN AND ITS CAUSE. 5 



SO that insects could be placed in the cage conveniently and also 

 for any necessary examination of the nuts during the test. 



The Schley and Curtis varieties were selected on which to con- 

 duct the experiment, owing to their apparant susceptibility to spot- 

 ting. 



The cages were placed in position during the last week of August 

 and the first week of September, 1921, in the vicinity of Thomasville, 

 Ga. From three to seven adult southern stinkbugs {Nezara viridula 

 L.) 2 taken principally from cowpeas and tomatoes, were placed in 

 each cage between September 1 and 15, except those used as checks. 

 This species of insect (Fig. 5) was used on account of its abundance 

 in the pecan belt of southern Georgia and also because of its fre- 



FiG. 3. — Highly magnified cross section of a kernel spot, showing the point of entrance 

 of the insect's seta and also the greatly ruptured and collapsed cells caused hy the 

 extraction of the oil and other substances from the kernel. 



quent appearance on pecan nuts. The writer has also observed a spe- 

 cies of Leptoglossus feeding upon immature pecan nuts, but has 

 made no attempt to determine its relation to pecan kernel-spot. 



At the time the bugs were placed in the cages the nuts of the 

 Curtis variety were immature, but had jiossibly attained their full 

 size. The Schley, being an earlier variety, was showing some evi- 

 dence of maturing, as indicated by a harder shell and some slight 

 discoloration of the shuck. 



Since the only object of using the insects was to determine the 

 relationship between insect punctures and kernel-spot, no attempt 



= Determined by W. L. McAtee, acting custodian of Hemiptera, U. S. National Museum. 



