84 
Indian Forest Records. 
[VOL. IX" 
fcorizontal ejection holes. The zone occupied by the workings of one 
grub may reach a length of 3 to 4 feet and the separate tunnels the 
thickness of one’s finger, e.g. ;• — 
Morns indica by Ayriona cinerea; Ficus asperrima, Careya 
arborea by Lamiid {Batocera sp.) 
(2) A restricted but irregular feeding area, partly under bark and 
partly in the wood — 
(a) Damage in the form of a canker, resulting in diseased or 
rotted timber and distortion of the plane of subsequent 
growth, e.g. : — 
Tectona grandis and Gmelina arborea by Haplohammus 
cervinns. 
(b) A close group of short (2") tunnels, e.g . — 
Tectona grandis by Sagra longicollis (Chrysomelidae). 
(c) Isolated bracket-or C-shaped tunnels, usually filled with 
fibres and occluded at each end, e.g . — 
Tectona graiidis by Aristobia birmanicum. 
(ii) Borers of felled or girdled trees. 
When a tree dies or is girdled or felled it is subject to attack by 
various classes of borers, which require the presence of bark for 
oviposition or for protection in the initial stages of their development. 
If the bark is removed from the tree immediately after death the 
timber is not liable to damage by insects of the following six classes : — 
Beetles. 
1. Longicorn Borers (Cerambycidae and LamiidaeJ. 
The larger longicorn borers feed as grubs in the early stages in the 
bark and sapwood; as they grow older the sapwood is more or less 
entirely destroyed and tunnels are extended deeper into the wood, 
the final tunnel or pupal chamber lying as a rule well within the 
heartwood at depths up_ to 6" from the surface. In the case of borers 
with an annual life-cycle the heartwood tunnel or pupal chamber, 3 to 
4 inches long and up to 1 inch in diameter, may be completed withia 
4 months after the eggs are laid. Borers with a six months cycle may 
complete their tunnels in 3 months. There is no succession of broods, 
although delayed emergence normally occurs, e.g. : — 
Shorea robusta by Hoplocerambyx spinicornis ; Hardwickia binata^ 
Soymida febrifuga by Aeolesthes holosericia ; Dipterocarpus’ 
turbinatus by Remphan hopei ; Sterculia villosa by 
Batocera rub us ; and practically all important timbers by 
various Cerambycidae or Lamiidae. 
[ 230 Q 
