THE PARAXDEA BOEEE AS AjST ORCHARD ENEMY. 5 



punctures are about 2 mm. deep by 1-2 mm. wide, and a single egg is 

 placed in each. (PI. Ill, fig. a.) After the egg is inserted the 

 mouth of the puncture is closed with fine particles of wood. Eggs 

 are deposited in this manner in groups of a dozen or less, placed close 

 together, in either the solid or somewhat decayed wood which forms 

 the walls of larval galleries or other openings in the tree where the 

 beetles can enter. When trees are first attacked the eggs are prob- 

 ably inserted from the surface into the wood of dead areas. 



The egg (PI. Ill, fig. b) is 1.5 mm. long by 0.5 mm. wide, oblong- 

 ovate, and creamy white. The surface is slightly granular. Eggs 

 hatch in two or three weeks, the time not having been definitely 

 determined. 



As soon as the larva or borer (PI. Ill, fig. c) hatches, it begins to 

 feed away from the original position occupied by the egg and extends 

 its gallery in a zigzag course through the wood (PL III, fig. e). 

 With the exception of the head, which is black, the borer is yellowish 

 white, but the body contents when feeding in dark-colored wood 

 give it a darker appearance. When full grown the larva attains a 

 length of about 1J inches. It grows slowly and probably remains 

 in the tree for at least three years before changing to the beetle, 

 although this point in the insect's life history has never been fully 

 determined. 



The galleries are packed throughout their length with dustlike 

 particles of wood that have passed through the digestive canal of the 

 borer. These galleries wind about in every direction and are usually 

 so numerous as to honeycomb the wood of the affected part of the 

 tree. (PL I, fig. d.) A single burrow may be several feet in 

 length, but its course is so tortuous that it seldom extends at any 

 point more than a foot away from the place where the egg was de- 

 posited. The usual general course is more or less directly into sound 

 wood from a place that is beginning to decay. This results in a rapid 

 enlargement of the area of decay and in the continuous extension of 

 the infested area with the appearance of each successive generation 

 of borers. In many infested trees examined by the writer the 

 Parandra borer was found to have been the first agency to open the 

 way for the spread of decay into beartwood. Other insects follow 

 but Less frequently precede them in their attacks on ( he heartwood of 

 fruit trees. 



When the larva i- ready to pupate it excavates a cell at the ter- 

 minue of it- burrow in the beartwood large enough to accommodate 

 it:^ body. Within this cell it transforms to the pupal stage (PL IV, 

 fig. &). The burrow \- packed for a short distance next to the 

 eell with coarse, stringlike fragments of wood. This excelsior-like 

 materia] form- the hod on which the pupa reposes and is evidently 

 provided to insure the drainage of any moisture thai mighl otherwise 



