MONOGRAPH OF THE GENUS SAPERDA 6$ 



as the round-headed appletree borer (S. Candida Fabr.) as 

 the galls would indicate the injury and could easily be cut off. 



Life history. The beetles [pi. 6, fig. 4] appear in New York 

 State during the month of June, the exact date varying according 

 to the season, the males preceding the females by three or four 

 days. They do not appear to eat and are short-lived, while the 

 whole brood, excepting the stragglers, appear and disappear 

 within the space of 10 or 12 days, so that close observation is 

 necessary in order to capture many. The late Dr J. A. Lintner 

 has taken this species June 25 at Schenectady, and Mr Moffat col- 

 lected beetles at Hamilton Ont. June 15, while Mr Zimmerman 

 records the capture of a female Aug. 15. 



The males watch for the appearance of their consorts and 

 pairing usually lasts three or four hours, according to Dr Ham- 

 ilton. The beetles fly but little and usually oviposit on the tree 

 they inhabited as borers, which explains the local character of 

 the species. The insects are sluggish and, when suddenly ap- 

 proached, drop to the ground and endeavor to conceal themselves. 

 Egg-laying probably occurs during the night, though the process 

 has not been observed. Small limbs, varying in size from | to i|- 

 inches in diameter, are selected for this purpose, and, according to 

 the thickness of the limb, the female uses her mandibles to make 

 from three to six longitudinal insertions through the bark, each be- 

 ing about | inch in length, parallel to one another and dividing the 

 circumference of the trunk or limb into nearly equal sections. An 

 egg is deposited in each of these slits, and as soon as hatched the 

 larva at once makes a burrow beneath the outer layer of the wood, 

 perhaps i inch in length, and uses this as a retreat from which 

 it issues to feed on the wounded tissue caused by the irritation. 

 These slits and the irritation caused by so much cutting produce 

 an increased flow of sap to the wound and a consequent thicken- 

 ing of the portions between the slits, so that the affected part 

 soon assumes a gall-like appearance. 



The work of this species is shown on plate 6, which represents 

 a twig on the lower portion of which are two old galls with 

 irregular, decaying, overgrown cavities [fig. 1], which are quite 

 different from more recent galls [pi. 6, fig. 2]. The borings of 



