2go 



FAMILY CERAMBYCIDAE 



This insect was taken in all stages of larva, pupa, and beetle in a 

 large pyinkadu-tree in a clearing close to the Salween 



Life History. River. The tree had been felled about a month pre- 



viously, and was still green. Specimens of the insect 

 were taken between the 8th and nth March 1905, The grubs feed in the bast 

 and sapwood, principally in the latter, as the bark of the tree is very thin. 

 The grubs were mostly fuU-grov/n at this period, but the majority of the 

 beetles were still immature. A few perfectly developed insects were, how- 

 ever, taken from the pupal chambers. 



The grubs feed at first in the bast and sapwood, eating out winding 

 galleries which become broader as they proceed. These galleries are tightly 

 packed with excreta and wood particles. Each gallery is distinct, but 

 when the grubs are as numerous as in this case the galleries are liable to 

 interlace at times. When more than half-grown the larva bores down into 

 the wood (at a, fig. 200), the tunnel down into the wood being straight at first 

 and then gradually curving until it again becomes parallel to the long axis 

 of the tree. A broad irregular gallery is then eaten out in the wood (as 

 shown in fig. b), which is closely packed with excreta and wood-dust. 

 When full-grown and ready to pupate the grub curves the gallery once 

 more, eating out a narrow chamber parallel to the long axis of the tree, but 

 deeper in the wood (c). This chamber is at times situated below the 

 portion b of the gallery. In this chamber, which is quite free from wood 

 particles and excreta, the larva changes to the pupa stage. 



^tLXKraXf*^^*^ W ^*4; 





Fk;. 200. — Larval gallery and pupating-chamber of Xystrocc>-a globosa, Oliv., in pyinkadu. 

 Salween River, Tenasserim. (E. P. S.) 



As I have said, the insect was taken in all the stages of larva, pupa, and 

 beetle, though no beetles had yet left the tree so far as I was able to 

 observe. It is probable that the beetles appear on the wing in April, and it is 

 perhaps possible that the insect passes through two generations in the year. 



Although in the tree in which it was found the insect was extremely nu- 

 merous, I was unable to find any predaceous or parasitic insects infesting it. 



The larvae, when numerous, completely destroy the bast layer of the 

 tree, and the insect must therefore be classed as a pest of some importance 

 so far as the pyinkadu is concerned. 



