12 BULLETIN 847, U. S. DEPARTINIEXT OF AGRICULTURE. 



which castings are ejected and from which a small quantity of sap 

 often flows. In some cases the borer burrows into the wood the first 

 season, but usually it does not enter the wood until the succeeding 

 spring. In small trees the galleries penetrate to the heart, bur in 

 old trees they are seldom extended more than an inch beneath the 

 inner bark. The burrows in the wood, like those in the bark, are 

 broad and irregular in shape and usually extend both above and 

 below the surface of the groimd. In the northern part of the in- 

 sect's range a greater proportion of the feeding seems to take place 

 beneath the groimd. The writer found larvae in Maine burrowing 

 downward in the roots to a distance of a foot or more from the 

 base of the trunk, a depth which does not seem to be reached in the 

 South. Many 1-year-old larvae were also found in Maine that had 

 not yet penetrated into the wood but were still feeding in the bark 

 near the old oviposition scars. In all their feeding larvae keep an 

 open space about themselves, to allow of free movement, but pack 

 the balance of their burrows with wood fragments. Strings of red- 

 dish-brown castings are also thrown out from the tree through small 

 openings in the bark. (PI. V,C.) 



In the late summer and autumn preceding the spring during 

 which pupation is to take place, the larvae excavate galleries leading 

 up the trunk of the tree a short distance beneath the bark. (PL VIII, 

 A. B.) At the upper end of this gallery the pupal chamber is 

 formed by slightly enlarging the circumference of the opening and 

 curving the upper end outward to the inner bark, (Pi. VII, A.) 

 The curved upper end is packed lightly with wood dust and a con- 

 siderable space in the gallery below the pupal chamber is filled with 

 short, excelsior-like strings of wood torn from the walls of the opening. 

 (PL VIII, A.) The space for the pupa is often 2 inches or more 

 in length and both the larvae and pupae when occupying it recede or 

 advance when disturbed, evidently a provision for escaping wood- 

 peckers. The pupal quarters usually are practically completed in the 

 autumn but the larvae add finishing touches in the spring before they 

 pupate. In small trees the exit holes at the upper end of the pupal 

 chambers are usually within from 4 to 8 inches of the ground, but in 

 large trees it is not unusual to find the place of exit at the terminus 

 of a gallery extending upward from the ground to a distance of 18 

 inches or 2 feet. Just why the pupal quarters should be made higher 

 in large trees than in small trees does not seem to have been 

 determined. 



Wintering larva? begin activities early in the spring and continue 

 to feed until stopped by the cold weather of winter. Probably the 

 annual feeding period in the South is much longer than in the North. 



