4 BULLETIN 243, U. S. DEPARTMENT OF AGRICULTURE. 



The egg gallery is usually kept straight and close to the axis of 

 the cone. During the early part of the season it has frequently been 

 observed that in the small cones, from 2 to 4 inches long, the adults 

 extend the egg gallery nearly to the outer end of the cone, depositing 

 four or five eggs along its length, and then bore out through the 

 scales and emerge. It has not been determined whether such emerg- 

 ing adults attack another cone or not, but it is reasonable to assume 

 that this is the case. In the larger cones, from 6 to 8 inches long, 

 which are attacked later in the season, from 15 to 30 eggs may be 

 deposited; and as this probably represents the minimum number of 

 eggs deposited by a pair of beetles, it is evident that very short cones 

 do not afford sufficient length of egg gallery for the deposition of this 

 number. Consequently a pair of parent adults may extend the egg 

 gallery through several of the smaller cones before the egg-gallery 

 capacity of the cone is exhausted. 



As the attack continues through the latter part of June, the size 

 of the attacked cones keeps increasing until the larger ones are from 

 6 to 8 inches long. The parent adults seldom emerge from these 

 larger cones and later in the season will be found dead in the end of 

 the egg gallery. By the 1st of July the new attack is complete. At 

 this stage the infested cones are from 2 to 8 inches long, while the 

 normal unattacked ones are from 10 to 18 inches long. The blighted 

 cones are brown and stand out conspicuously on the trees. The 

 seeds seldom form when the smaller cones are attacked, whereas the 

 seeds of the larger cones that are attacked may reach two-thirds 

 normal size and the outer shell may harden, but they never fill or 

 mature. 



Immediately after hatching the young larvae begin to feed upon 

 the scales and tissues of the now withering cone. They feed in such 

 a manner as to leave no distinct lateral larval galleries. If the 

 cones are opened during the larval period the small white grubs 

 may be found in any part of the cone, the axis, scales, and often in 

 the tender milky seeds (PL II, fig. 3). The development of the 

 larvae is very rapid. Pupa? may be found in the cones within four 

 Aveeks after the first attack. By the last of June the cones which 

 contain pupae are dry, withered, and reddish brown in color. At 

 about this stage the dry, withered stalks begin to break from the 

 limbs and the blighted cones fall to the ground. All sugar-pine 

 cones which are attacked fall from the trees before the close of the 

 season and the broods complete their development in these fallen 

 • •ones. The pupae transform to new adults, which begin to appear 

 by July 10, and this transformation continues throughout the sum- 

 mer, until by the middle of August the majority of the broods have 

 reached the stage of new adults. Practically all of the infested cones 

 have fallen by this time and the brood remains in these cones through 



