358 DINODERYS MINUTUS. 
the 2nd about 4-5 weeks, from the third week in June 
to near the end of July ; the 3rd 4 weeks, from the end 
of July tothe beginning of September ; the 4th less than 
4 weeks, from Ist week in September to end of the 
month; the 5th from end of September to end of Octo- 
ber, It is probable that many of the beetles of this 
generation were caught and killed off by the cold snap 
experienced towards the end of the month. 
Protection. 
As detailed in a note published elsewhere * my experiments 
and observations were initiated in order to enable me to advise 
the Superintendent of the Government Telegraph Workshops 
as to how to protect a large number of bamboos which he was 
converting into field teleyrapk poles. 
I may requote here from my previous note :— 
Towards the end of April of this year Mr. Williams, the 
Superintendent of the Telegraph Workshops at Calcutta, 
informed me that bamboos which he was converting into field 
telegraph posts for use on frontier expeditions and elsewhere 
were being attacked and riddled by insects. Thespecimens he 
sent me I identified as the common bamboo-boring beetle 
(D. minutus). As the question of the preservation of bamboos 
against. this insect had been engaging my attention for some 
time, I immediately paid a visit to the workshops and examined 
the bamboos. I found that they were being experimentally 
treated in the following manner before being fitted up as tele- 
graph posts :— 
(1) Five days’ soaking in river water ; 
(2) five days’ soaking in a solution of copper sulphate, 
after which they were dried in a covered shed 
for several days; and then 
(3) soaked for 24 hours in common Rangoon oil. 
This latter has the effect of darkening the bamboos and the 
smell of the oil remains in them for some considerable time, 
* A Note on the Preservation of Bamboos from the attacks of the bamboo 
beetle or “ Shot-borer.”” Appendix Series, Indian Forester Vol. XXIX, No. 12 
(1003). 
