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A NOTE ON THE PRESERVATION OF BAMBOOS FROM THE 

 ATTACKS OF THE BAMBOO BEETLE OR " SHOT-BOP.ER." 



BY 



E. P. STEBBING, F.L.S., F.E.S., 



Officiating Superintendent, Indian Museum. 

 General Remarks. 



The work of the bamboo beetle or " shot-borer," the gJioong of the natives 

 in many parts of the country, is wellknown in India. All who have anything 

 to do with bamboos, either with their cutting and export, their use in buildings, 

 or their manufacture into the thousand and one articles to which this most 

 useful commodity is put in the country, have to count upon and allow for the 

 ravages of this pest, and in many parts a year to a year and a half may be given 

 as the estimated and probable life of a bamboo after cutting. 



Description and Life-History of the ' Shot-Borer.' 



But although the results of its work are well-known, the real author of the 

 depredations is far irom being a well lecognised enemy owing both to its small 

 size and to its secretive habits. The damage is committed by a tiny beetle and 

 its grubs, which are just of slightly smaller diameter than the holes with which 

 the bamboos are seen to be riddled. The beetle, which has a black head and 

 thorax and reddish-coloured shining wing covers, bores its way into the 

 bamboo, and lays its eggs in the interior, each beetle laying about 20. From 

 these eggs small, white, roundish dots of grubs issue within a few days of their 

 being deposited. These tiny larvae burrow up and down in the interior of the 

 bamboo, and reduce its structure to powder. About four weeks are spent in 

 this stage, and the grubs then enlarge the ends of their burrows and change to 

 pupas which after some eight days or so turn into the beetles. On becoming 

 mature the beetles bore their way out of the bamboos and thus add further to 

 the tunnels already made in them. On emergence the insects fly off to attack 

 fresh bamboos or they may bore into the one in which they have matured 

 themselves. There are thus three separate forms of attack : — 



(a) The female beetle bores into the interior of the bamboo and lays its 



eggs there. This is the first attack on the bamboo. 



(b) From the eggs hatch out little grubs which feed upon the wood of 



interior of the bamboo and thus undermine its strength. 



(c) The beetles on maturing from the grubs bore their way out of the 



bamboo. 

 It used to be thought that each of the shot-borers made their way out by a 

 separate tunnel, driven direct from the place where the grub had pupated to 

 the outside. This is not however the case, as the matured beetles appear to 

 issue either all from the same exit hole or from one or two only, these being 

 often the former entrance holes of the mother beetles which are considerably 

 enlarged. Beetles of the new generation appear to also make use of these old 

 holes to enter the bamboo to egg-lay, boring away from the old gallery when 



