-DINODERUS MINUTUS. 36r 

(4) That bamboos cut in the forests between December 
and February can, even if not treated till between two and three 
months after cutting (by which time it is probable that many 
of them will contain eggs) be preserved by the oil-treatment 
from further attacks of the April, June, July, September and 
October generations of beetles, each of which attacks means. 
their subsequent riddling by the larve arising from the eggs laid 
by the beetles. 
(5) That the oil-treatment, therefore, considerably prolongs 
the period of usefulness of the bamboo, this period being, as 
far as the experiments at present show, at least a year. 
Plate XXI, 1-4, shows lengths of bamboos which had been. 
put through the preservative treatment and converted into tele- 
graph posts. It was suksequently shown that the reason why 
these lengths were attacked by the beetle was due to the fact 
that they were the top ones in the oil tank and had never 
received a thorough soaking in the oil. In fig, 1 the entrance 
holes blocked by ejected bamboo wood dust are clearly visible 
while 2-4 show the damage done to the internal structure of 
the bamboo by the borings of the beetle and its grubs. Fig. 
5 shows a section of a larger bamboo opened out flat to show 
the attacks of the beetle and grubs, Fig. 6 shows a well- 
soaked bamboo which had been enclosed for several months in 
the special boxes made for the purpose, together with several 
lengths of attacked bamboos. It remained entirely unaffected. 
Recommendations. 
(z) I am inclined to recommend that the soaking for five 
days in water should be continued, since a thick shiny gelatinous 
substance exudes from the bamboos during this process, and this 
exudation probably enables the bamboo to absorb a_ larger 
quantity of oil than would be otherwise the case. 
(2) That the soaking in the copper sulphate solution be 
discontinued, since the experiments have shown it to have no 
preservative effect against the beetles. 
(c) That the bamboos be allowed to dry ina covered shed. 
for several days after the water process. 
C 
