330 FAMILY CERAMBYCIDAE 



The damage committed by Hoploceyamhyx in the forests is of a two- 

 fold nature : (i) The grub feeds in and destroys the 

 ^^rthe^FrrTsr"^ ^^'^st layer of the trees, thus eventually killing the tree ; 

 (ii) the grub tunnels down into the heart-wood and 

 thus spoils or ruins it for commercial purposes. 



The beetles, beyond enlarging the exit-holes in the bark to enable 

 them to leave the tree, do no actual harm to it. The damage is of 

 the same nature both in Assam and the Central Provinces and neigh- 

 bouring sal areas. In both the insects must be regarded as a most 

 serious pest. 



It is probable that in Assam, owing to the hotter and moister climate, 



„ ^ n .... the life-cycle is shorter, and therefore the beetle in- 



Damage Committed ■> i • a 



in the Assam and creases with the greater rapidity. Also in Assam the 



Eastern Bengal creepers have a much more luxuriant growth, and tend 

 Sal Belt. ^Q induce sickness and loss of vitality in the trees to a 



much greater extent, and thereby engender a state of growth particularly 

 favourable to the attacks of the cerambyx. Observations would seem to 

 show that this creeper growth is one of the greatest dangers the trees 

 have to contend with in these forests. Not only is it in itself parti- 

 cularly harmful, eventually strangling the life out of the tree, but, 

 if cut back too late, the tree has lost so much vitality that it falls an 

 easy prey to both the longicorn beetle and the bark-borer Sphacrotrypcs 

 (p. 481). 



Besides being a serious menace to the trees themselves, the beetle is 

 equally noxious as a pest to the timber, and, unless barked, the wood of the 

 trees felled in the forest will be found to be full of the larvae within two or 

 three months. Both logs and sleepers examined in the Hultugaon and 

 Kachugaon forests of the Goalpara Division and the sal areas round 

 Rajabhatkhowa in the Buxar Duars Division were found to contain the 

 tell-tale holes made in the wood by the larvae of this pest ; and Mr. Perree 

 has informed me that the depredations of the insect are now so well known 

 and are of so damaging a character that the most serious losses are suffered 

 if barking is not undertaken at once. 



I think it may be taken as proved that the beetle will not lay eggs 

 in dead bark or even in bark of trees felled two or three months before it 

 appears on the wing, nor will it lay in dry wood. That the beetle lays 

 eggs in standing green trees was proved by Mr. Perree himself showing 

 me a tree of this description which bore evidences of being attacked by 

 the beetle. Woodpeckers had bored circular holes into the bark in several 

 places to get at the grubs or pupae {vide fig. 222). The tree had a girth 

 of 3 ft., and the top was absolutely green. We felled the tree and split 

 up the last eighteen inches of the stump above ground. In it were two full- 

 grown larvae pupating in their newly constructed pupal chambers, each 

 chamber being covered with a newly formed calcareous covering and having 



