BUPRESTID-BEETLES, 59 



is a peculiar worm, with an almost thread-like, pale-yellowish or 

 white body, with the anterior segment enlarged and flattened. 

 The small head is brown, the powerful jaws are black, and the 

 tail is armed with two slender dark-brown horns, each with 

 three blunt teeth on the inner edge. When this worm is mature 

 it measures about six-tenths of an inch in length. But not all 

 the worms form such galls ; many can be detected in canes not 

 showing any swellings. 



While still young the larvae inhabit mainly the sap-wood, 

 and following an irregular spiral course, they frequently girdle 

 and destroy the cane. In most cases a number of worms are 

 found in a single cane. Early in May the full-grown larva en- 

 ters deeply into the pith of the cane, and here it changes to a pupa, 

 from which the adult escapes soon afterwards. 



The eggs are deposited early in summer, mostly during the 

 month of July ; they are laid on the young canes. 



Fig. 66.— Agrilus ruficollis. Fab. After Riley. 



The beetle is a rather beautiful insect with velvety brown- 

 ish-black wing-covers, a rather small, dark, bronzy head, and a 

 very bright coppery neck or pro-thorax ; the underside is of a 

 uniform shining black color ; it measures about three-tenths of an 

 inch in length, and is shown in Fig. 66. 



Prof. Smith, who has closely studied the life-history of this 

 beetle, writes that "it is good practice to cut out all galled canes 

 early in spring, and bum them. Trimming is done at this time as 

 a matter of regular cultivation, and the galls are then easily seen. 



