100 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. 



it eats its way out at or just above the bottom of the egg and begins 

 to feed along the under surface of the bark. When first hatched 

 the hu'va^ are slightly longer than the egg but are less in diameter. 

 After emerging from the eggshell they are found lying in a slightly 

 curved position in the larval burrows. At first they are white but 

 soon assume a pinkish tinge due to the bark in the digestive tube. 

 The larvae at first feed slowly and are several days getting away 

 from the eggshell but progress faster as they grow larger. As 

 they work out of the eggshell the sawdustlike excrement passed 

 through the body fills these and holds them in place as the larva? 

 work out. The excrement voided by the larvae marks their path, 

 appearing like very fine sawdust. 



The larvae work away from the brood chambers at right angles, 

 folloAving, for the most part, the grain of the wood. For from one- 

 half to three-fourths of an inch the larval burrows lie side by side, 

 but later they diverge, so that the exit holes (PI. X, fig. 2) form an 

 irregular ellipse around the brood chamber. The larval burrows 

 measure from 1-i- to ^^ inches in length. When about to pupate in 

 bark, wdiich is about one-eighth of an inch or more in thickness, the 

 larva? W'Ork toward the outer edge of the bark and there form pupal 

 cells. In these cells the larvae continue to develop from one to three 

 or more days before casting the skin and becoming pupae. 



Some 25 to 30 days are required for the full development of the 

 larvae. At the end of this time, having finished feeding, they void 

 the excrement before pupating and have then a white appearance. 

 Through the life of the larvae the head is covered with a fine yellow^- 

 ish pubescence, which is more abundant about the mouth parts than 

 elsewhere. (Full-grown larva, fig. 20, d.) 



Description of fuU-groicn larva. — Length, 2.15-2.75 mm.; width across thorax 

 (widest part of insect), about 1.10 mm. Head subelliptical, about O.G mm. wide, 

 yellowish, apex lighter: mandibles brownish, dark at tip. Body white, curved, 

 tapering from thorax to rounded caudal end, quite wrinkled; legless, but on 

 ventral surface of thoracic segments a small group of setiie at points of position 

 of the adult's legs. Head with a few sparse setae and a few on body. Body 

 covered all over with many minute, short, stout spines. 



THE PUPA. 



The pupae (fig. 20, e) are quite active, moving the abdomen con- 

 tinually back and forth. From 4 to 10 days are spent in the pupal 

 stage, the pupa gradually assuming a dark color. Wien the pupal 

 skin is cast, the beetles are very tender; they require from 4 to G days 

 to completeh' harden and usually do not cut their way out from the 

 pupal cells until they have fed a little, after which they remain in 

 the pupal cells for from several days to two weeks longer. 



