DISEASES AND PESTS 77 



half of its length. It eats a channel through the soft 

 wood or the heart of the tree, the channel necessarily 

 widening as the larva grows. The larva begins its life 

 inside the tree, and normally never comes to the surface. 

 Therefore, neither it nor its work is directly to be seen. 

 It can sometimes be heard if the ear is held closely 

 against the outside of an infested trunk. As a rule, the 

 first indication of its presence is the appearance of 

 mutilated leaves or the collapse of young leaves. A 

 tree badly infested by these larvae may be expected to 

 be killed, promptly or slowly, by the destruction of its 

 heart. Young leaves may simply cease to appear, or 

 may be killed one at a time after they appear, or the 

 younger part of the crown may be undermined so that 

 it falls out. 



The head of the larva is brown, rather large, and 

 without eyes. Its body is white, and is thickest behind 

 the middle. It has thirteen segments. The surface is 

 velvety in appearance, and much wrinkled. Scattered 

 all over the body are shiny spots, each of which bears 

 one bristle, excepting the spots on the next to the last 

 segment, which bear six bristles each, and four pro- 

 tuberances, each with two longer bristles, on the last 

 segment. The larva is without real legs. As usually 

 found, it is curved strongly downward. 



The cocoons of Rhynchophorus are made of coarse 

 coco-nut wood fibres, closely woven together. They 

 are elliptical in outline, 5 to 12 centimetres long, 

 and more than half as much in diameter. They are 

 numerous in badly infected trees, sometimes being 

 found in the thick bases of the petioles, whence the 

 adult will be able to escape directly into the air. They 

 have always been described as formed close to the 

 surface, but in decaying crowns are produced at the 

 last points reached by the larvae, where the tissues are 

 just softened, at whatever depth from the surface of 

 the trunk. Within the cocoon is the pupa, showing all 

 the parts of the adult. 



There is a wide difference of opinion as to the time 



