12 
curving toward the first, without change of position by the insect. The 
ovipositor, however, is thrust in at a very considerable angle from that 
assumed in the first case, so that it crosses beneath the bark the cut 
first made, and the narrow intervening bark between the two iucisions 
is cut entirely loose. This has a very important bearing on the subse- 
quent condition of the wounds made by the insect in oviposition. The 
object is doubtless to cause a certain cessation of growth between the 
two rows of eggs, to prevent their being crushed and choked out by 
the rapid growth of the twig, and it is due to this peculiarity that the 
injury to the young limbs later assumes so serious 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 incisions and the 
killing of the intervening bark, causing 
it to adhere to the wood, a large scar 
is produced, which, with each subse- 
quent 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 broken off by the wind, and are 
very liable to attack by wood-boring 
insects. (See Fig. 7, e.) After conrplet- 
ing the two complementary slits and 
filling them with eggs, the female rests 
a considerable time before again begin- 
ning operations. The number of eggs 
deposited by a single female exceeds 
100, and possibly 200. Bather late in 
the fall a female which had just 
finished a pair of slits which contained 
some 20 eggs was found to still contain 
40 eggs in her ovaries. The adults first appear about the middle 
of July, and become most numerous during August and September. 
They begin oviposition about the middle of August, or even earlier, 
and continue this work until they are killed by the frosts of early 
winter. In Kansas I have found them busily ovipositing as late as the 
24th of October. The eggs remain unchanged or dormant in the twigs 
until the following spring, hatching in May or early in June. 
The eggs of the buffalo tree-hopper are subject to the attacks of at 
least two minute egg-parasites. One, an undescribed species of Cosmo- 
coma, Miss Murtfeldt reports had destroyed the larger proportion of 
eggs sent her from various localities in Missouri. Mr. Jack probably 
refers to the same parasitic insect which he says he observed, Septem- 
PlG. 7. — Ceresa bubalus Fab.: Twig, of 
apple slio wing: a, female at work; b, recent 
egg-punctures ; c, bark reversed with eggs 
in position, slightly enlarged ; d, single row 
of eggs still more enlarged; e, wounds of 
two or three years' standing on older limbs 
(adapted from Marlatt.) 
