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The attention of the Department of Entomology of the State Univer- 

 sity here was first caHed to the matter in late summer last year, when 

 a farmer brought a girdled branch to the laboratory. The girdling 

 plainly showed that it had been done by Oncideres, and later on one or 

 two specimens of the insect were secured. While no serious danmge has 

 been reported this season, many trees planted for shade have suffered 

 considerably, and there is evidence that the insect is spreading. Trees 

 that are the worse affected this year show a relatively small number of 

 last season's scars. The elms on the university campus continued to 

 drop their branches for four weeks or more, every moderately strong 

 wind bringing down fresh ones. 



On the fourteenth of September your correspondent visited the farm 

 of Mr. Harvey, near Blue Mound, to make observations on the work ot 

 the girdler. Some of the shade trees in his yard looked as if they had 

 been i)runed of nearly all the limbs ranging in size from onerfourth ta 

 one-half of an inch in diameter, the ground underneath being quite 

 covered with them. Owing to thebrittleness of the heart wood in elm, 

 the branches always fall oft" with the first breeze that sways them after 

 they have been girdled deep enough. Though some of the trees stood 

 in the edge of an apple orchard, the aj^ple trees were not affected. Mr. 

 Harvey stated, however, that he had noticed one girdled cherry limb 

 and two or three of a locust. As these trees stood beneath taller elms, 

 it is probable that the girdling was a mere accidental circumstance. 



A girdler being found at work, her performances were watched for 

 more than half an hour. She stood upon the part of the limb that 

 would fall, clasping the groove with the front tarsi, and working slowly 

 around, sometimes to the right and sometimes to the left, deepened the 

 channel, though not perceptibly, of course, at each round. The work 

 was nearly comijleted when she was first seen, the groove having 

 reached the heart wood and being about one-eighth of an inch in width. 

 When working on the under side of the limb, she would face about once 

 in a while and, to all appearances, dislodge chips from her mandibles. 



From the fact that the insect is almost invariably found on the 

 freshly fallen branch, one might infer that through instinct she always 

 stands beyond the notch and facing the tree so that she may go down 

 with the branch and finish her ovipositing in case she had not already 

 done so. In nearly every case that came under my observation, how- 

 ever, the egg-laying was finished when the branch fell, and the insect 

 was found either resting or feeding on the tender bark near the end of 

 a twig. In one instance, at least, the girdler was still ovipositing when 

 the branch was picked uj) an hour or so after it had fallen. Numerous 

 gnawed places on the tender side shoots attest to the quality of a work- 

 ing beetle's appetite. 



The line of girdling is usually very regular, and curves around the 

 limb nearly at right angles to its longitudinal axis. Very rarely an 

 uuskille«l Avorker fails to make exact connections in coming around tO' 



