35 
Part III.] Beeson : Beehole Borer of Teak. 
1—1J inches long and £ to £ of an inch wide. A minute ejection hole and 
connecting gallery is maintained, through which particles of bark and 
wood dust and excreta are ejected. A careful scrutiny of the bark at 
this period will reveal a slight accumulation of dust in a fissure in the 
bark ; the dust derived from the bark and first ejected is dark in color, 
while that ejected later, when the sapwood is reached, is white. If 
sap is abundant the particles of dust become gummed into small nodules 
and may hang in a bunch or loop from the ejection hole. 
Mr. Unwin, whose observations made in June, 1916, agree with the 
above, records a case of one larva that apparently abandoned its 
original burrow and constructed a new one. He notes that 4e although 
the larva itself was fully \ an inch long, the hole was not more than £ 
of an inch deep in the bark.” 
Construction of the Sapwood Chamber and Beehole. 
[Plate iii. Figs. 6, 7]. 
As the larva grows, the size of the bark and sapwood chamber is in¬ 
creased, both laterally and longitudinally and during the 3rd instar 
(if not earlier) it commences to bore a tunnel towards the heartwood. 
Numerous examples have been found of shallow sapwood chambers 
from which a gallery 1—2 inches long and £ of an inch in diameter 
extends inwards and upwards ; such galleries represent early deaths 
due to parasitism, and contain usually the cocoons of hymenopterous 
parasites with the skin of the dead ceramicus larva. In the next instars 
the heartwood gallery is gradually excavated almost to the full length 
of the final beehole, and is only slightly extended and widened during 
the later stages of the larval life. The gallery always runs upwards 
and is more or less straight, but may show a spiral or sigmoid tendency. 
Its diameter is increased with the growth of the larva, but is always 
wide enough for the larva to turn round. It is apparently used as a 
retiring or moulting gallery. 
The chamber in the bark and sapwood varies very much in shape and 
area ; its usual form is a stellate or lobed excavation the arms of which 
extend into the living bark and outermost layers of sapwood; in its 
centre its depth is greater and increases in a funnel-shaped impression 
towards the mouth of the heartwood tunnel. In slow-grown trees the 
superficial extent of the sapwood chamber of k.rvae of equal ages is 
usually greater than in quick-growing trees ; a typically developed 
chamber is about 3 inches square but shallow straggling burrows 
may occur 5 inches long. Over one or more of the arms of the larval 
chamber circular ejection holes are constructed, which when not in us$ 
£ 263 JJ e$ 
