NOTES ON CERESA BUB ALUS, Say. 



BY JOHN G. JACK, CHATEAUGUAY BASIN, QUE., CAN. 



Read before the Montreal Branch Entomological Society of Ontario, 9th February, 1886. 



During the past two years, but more especially this season, we have been very much 

 troubled and annoyed by the attacks of the Buffalo Tree-hopper (C. bubalus Say) on the 

 young trees in the orchard. Most of the trees have been seriously injured by having the 

 bark cut up by the ovipositors of these insects, when depositing their eggs. These incisions 

 and the eggs in them were so numerous that in many cases it was impossible to raise the 

 bark for the purpose of "budding " the trees. 



The incisions and eggs are usually most abundant on the south and upper side of the 

 limbs, comparatively few being found on the shady or under sides. The first imagines 

 were noticed in the orchard on July 16th, and a few days later they became quite abundant. 

 On the young tender twigs of the apple trees, especially those nearest to the ground, large 

 numbers of the insects were found busily extracting the juices with their tender beaks. 

 Upon close examination the twigs plainly showed the traces of their punctures. They 

 were also very abundant on beans, potatoes and several kinds of weeds, in many cases 

 completely covering the steins, and all engaged in feeding upon the juices of the plants. 

 Bean-stalks that were attacked in this way were considerably injured, as numerous dark 

 knotty formations occurred at the places that were much punctured, so that the growth of 

 4 the plant was decidedly checked. 



The insect was first noticed depositing eggs about August 1 2th, and a few incisions 

 were then to be found on the branches. This depositing of eggs continued until October 

 8th, when a severe frost killed a great many of the tree-hoppers, although a few escaped 

 and continued the work until October 26th. After that date they were not noted. 



Some of the eggs of the season of 1884 were collected last spring and kept in a very 

 tight box. They were hatched during the first week in June, and with them were a 

 number of small Dipterous flies, evidently parasites upon the eggs of Ceresa. I watched 

 for these parasites in the summer and autumn, and first found them August 31st, on limbs 

 where the tree-hoppers were depositing eggs. The parasites were found in larger numbers 

 a little later, and I had the satisfaction of distinctly seeing a number of them insert the 

 abdomen and sometimes almost the entire body deeply into the gaping slits made by the 

 ovipositors of the tree-hoppers. Professor Riley thinks that the parasite may be an 

 undescribed species. 



As I did not know the best conditions or food for the young larva? of Ceresa, I placed 

 them in a glass jar and gave them the tender twigs and leaves of apple trees. From these 

 they seemed to extract the juices, and they could be seen in rows on the ribs of the leaves, 

 with extended beaks, while little particles of a clear gummy substance were often found at 

 the places where the insects had been sucking the juices. I afterwards added bits of 

 grasses, etjc, to their food, but after some time they ceased feeding, and finally they all 

 died, none of them being more than half grown. This was about July 5th, and about this 

 time I found a number of the larva? about some raspberry canes in a shady place, and on 

 July 13th I took more of them among low juicy grasses and thistles, growing thickly in a 

 cool, moist place, several rods from any trees of any kind. On July 17th, nearly all these 

 larvae changed to the adult form. 



The larva becomes much elongated as it begins to cast the last envelope, and one of 

 them, noticed when just beginning the operation, took three hours to complete it. 



The full grown larva is about 8 m.m. in length, and light green in colour, somewhat 

 lighter than the mature insect. The young larvae appeared to be of a darker green than 

 they were at a later period of their growth. The general shape is triangular, like that of 

 the mature insect, but the broad horn-like projections are not seen in the larva. The eyes 

 are prominent. On the front of the elevated thorax, and behind each eye, are two short, 

 strong spines, one above the other, armed with several lateral prongs or forks ; higher up, 

 near the apex of the triangular shaped thorax, are two more, somewhat larger armed spines, 



