INSECTS FEEDING ON BARK AND DEAD WOOD. 



171 



THE ORANGE SAWYER. 



(Elapliidion inerme Newman.) 



4 



This insect has been described in Chapter VIII, and is there shown to 

 be injurious, under a careless sys- 

 tem of pruning, in which the ends 

 of branches are left untrimraed, 

 with sufficient dead wood to at- 

 tract the parent beetle, but not 

 enough to support the larvae ; so 

 that the latter are driven by hun- 

 ger to enter and feed upon the liv- 

 ing wood. It appears, therefore, 

 that under natural conditions this 

 beetle is merely a scavenger. Its 

 grub feeds upon the wood of many 

 trees, and, like most members of 

 the Longicorn family, thrives only 

 upon diseased and devitalized tis- 

 sues, or upon wood which, though 

 dead, has not entirely parted with 

 its sap and become hard and dry. 



Fig. 80 represents the larva of 

 E. parallelum, a closely allied spe- 

 cies, having the same habits as the Orange Sawyer, but which lives in 

 the Oak, &c. 



THE ORANGE FLAT-HEADED BORER. 



(Chrysobothris chrysoela 111.) 

 [Plate XIV, Fig. 8.] 



Dead twigs and branches of Orange are frequently found, upon which 

 the bark is cracked and loosened, so that it comes off at a touch, bring- 

 ing away with it considerable dust from the wood lying immediately 

 beneath, a thin layer of which has been reduced to powder. When the 

 loose bark and sawdust are removed, the surface of the branch presents 

 an eroded appearance, indicating the path of an insect. The edges of 

 the track form a succession of semicircular curves, as if made by the sweep 

 of a miniature scythe. It is, in fact, the gallery of an extremely thin- 

 bodied grub or sawyer, made partly in the bark and partly in the wood, 

 and always filled with comminuted wood, which has passed through the 

 digestive organs of the grub, and has been voided and deposited be- 

 hind it as the insect made its way through the wood. The cell in which 

 the pupa is formed is excavated in the solid wood. It lies parallel with 

 but beneath the gallery, with which it is connected at one of its ex- 



ant 



FIG. 80. Elaphidion parallelum : a, larva from 

 above ; b, from beneath ; /, ligula-like process, 

 behind the labial palpi ; Ibr, labrum ; mx, maxilla ; 

 mx', meutum ; ant, antemia. (After Packard.) 



