9 



away with a loud buzzing noise from the trees approached, aud, as it 

 is a very shy insect, there is some difficulty in coming close enough to 

 see it at work and observe its methods. Once well engaged in oviposi- 

 tion, however, it becomes for the time being fearless and may be closely 

 watched, even under a band lens. 



The Department has received rather frequent reports of damage by 

 this insect of late, in such states as Kansas, Iowa, Illinois, and Missonri. 

 The smaller limbs of trees are often completely scarified over their 

 upper and lateral surfaces, so that the trees become dwarfed or bark- 

 bound, make a sickly growth, and are rendered more liable to the 

 attacks of wood-boring insects. This latter source of injury was first 



Fig. 4. — Ceresabubalus Fab. : a, female; 6, enlargement of anterior foot of same; c, do. of antenna; d, 

 do. of wing; e, last ventral segment of female; /, ventral view of tip of abdomen of female, showing 

 terminal segments and ovipositor ; g, do. lateral view ; h, penultimate ventral segment of male ; i 

 ventral view of tip of abdomen of male — all enlarged (original). 



prominently brought to our notice in a communication from Mr. J. A. 

 Pettigrew, superintendent of Lincoln Park, Chicago, who described 

 the attacks of a borer in the smaller branches of the cottonwood {Pop- 

 ulus monilifeya), which caused the limbs to break off and fall to the 

 ground in great numbers. Examination of the twigs submitted by 

 him showed at once that they had been oviposited in very abundantly 

 by the bu£fc\lo tree-hopper a year or two before, and that the old scars 

 from the egg-punctures of this insect had furnished favorable condi- 

 tions for the attacks of a wood-boring beetle, Oherea scTiaumii Lee. Tliis 

 beetle had deposited its eggs in the diseased points left by the Ceresa, 

 and the larv.ie of the beetle had burrowed up and down the twigs, weak- 

 ening them andcausing them to break off and fall as described. Healthy 

 twigs would be distasteful or unsatisfactory to this insect, but the 

 diseased condition, and particularly the dead spots left by the Ceresa, 



