cut entirely loose. This has a very inii)ortant bearing- on the suljse- 

 quent condition of the wounds made by the insect in oviposition. 

 The object is doubtless to cause a deadening of the wood between 

 the two rows of eggs, to j^revent their being crushed and choked out 

 by the subsequent rapid growth of the twig, and it is due to this 

 peculiarity that the injury later assumes so seriovis a nature. A 

 single incision made by the insect to contain its eggs would heal over 

 and cause little after-damage, but with the combination of two incis- 

 ions and the killing of the intervening bark, causing it to adhere to 

 the wood, a large scar is produced, which, with each subsequent 

 year's growth, enlarges and ultimately assumes an oval form, the 

 dead bark of the center breaking out. After a few years, limbs which 

 have been thickly worked on by the insect become very scabby and 

 rough, are easily l)roken off by the wind, and are very liable to attack 

 by wood-boring insects (fig. 2, e). 



The adults first appear about the 

 middle of July, and become most num- 

 erous during August and September. 

 They begin ovipositicm about the mid- 

 dle of August, or even earlier, and con- 

 tinue this work until they are killed 

 by the frosts of early winter, some- 

 times working as late as the end of 

 October. The number of eggs depos- 

 ited by a single female exceeds 100, and 

 possibly 200. The eggs remain un- 

 changed, or dormant, in the twigs until 

 the following spring, hatching in May 

 or earh^ in June. The egg is about 

 one-sixteenth of an inch long, slightly 

 curved, tapering towards the outer end 

 and more rounded at the inner one. It 



„ , , ,. , , , . ■ f , is without markings, of a dirty, whitish 

 Fig. 4.— Cereso Ijubulus. : twij^ of apple . . 



showing: a, female at work; 7j, re- color, and cylindrical, except as more 



recent egg-punctures ;^l3ark reversed j angulated by the pressure of 



with eggs m position, slightly enlarged; '^ . 



d, single row of eggs still more enlarged; the WOod and the adjacent eggS, 



c, wounds of two or three years' stand- rm i! j.i i ' .ce i j. i 



ing on older limbs (author's illustration). The eggs of the butfalo tree-hopper 



are subject to the attacks of at least two minute egg parasites, which 

 often do much to keep the insect in check. 



In general characteristics the larvse and nymphs resemble the 

 adults, but are wingless and covered along the center dorsally A^th 

 numerous forked or barbed projections. 



