Cerambycidae 475 



Family cerambycidae 



THE PAINTED HICKORY BORER, 

 CY'LLENE CARYAE* 



THE hickory borer is a sun-loving insect. On bright, sunny days 

 during May and June adults may be found on the trunks and 

 branches of recently killed trees or on felled timber, running rapidly 

 back and forth. Rarely are they found on such material when it is 

 well shaded. 



Like many of the Cerambycidae, the adults of this species are pollen 

 feeders. For some time the writer was puzzled as to what the food 

 plants of the beetles could be, for while males and females copulated 

 freely when confined in cages, oviposition did not occur, and both sexes 

 died in three or four days when no food was supplied. Finally, the 

 beetles were found actively feeding on the pollen of the flowers of 

 hawthorn {Crataegus sp.). From then on no difficulty was experienced 

 in breeding the insects in captivity. With a supply of these blossoms in 

 the cages, copulation took place and eggs were promptly deposited. 



Mating occurs shortly after emergence. Adults which emerged June 

 6 were found copulating the following day. Oviposition takes place 

 very soon after copulation. Females which were observed mating on 

 June 13 deposited eggs the following day. The eggs are always placed 

 in crevices or under scales of the bark. 



In branches with very smooth bark slits were cut which provided 

 favorable places for the deposition of eggs. The branches were placed 

 in cages, each of which contained a single fertilized female. In the 

 insectary the number of eggs placed in a single crevice varied from 

 1 to 14. 



The eggs hatch in from 6 to 10 days. When a large number are laid in 

 a single crevice there is not room enough for all to get started. Ac- 

 cordingly, when two or more penetrate a single burrow, one is punctured 

 by the mouthparts of the other and killed. Out of 52 larvae hatching in 

 a single piece of hickory, only 12 were able to survive and complete 

 their burrows. Moreover, when the bark is smooth and no crevices or 

 scales are present to serve as braces for the larvae in beginning their 

 burrows, they are unable to penetrate the bark and soon die. In like 

 manner, the larvae are unable to burrow into material from which the 

 bark has been removed. 



The larva becomes full grown in from 10 to 12 weeks. At the end of 

 that time it gnaws a large, oval-shaped hole through the bark to the 



♦Abstracted from Cornell Univ. Agric. Exper. Sta. Bull. 407:175, 1921, by E. H, 

 Dusham, Pennsylvania State College, 



