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extremely small TEENY, and may perhaps eye consisted of 
glucose, as it may have been insufficient to detec y Fehling’s 
reaction in the Saat amount of material used for examination. 
The quantity of starch is, on the whole, considerable, though 
decidedly less than in the other specimen, and also varying a 
good deal locally. Starch had precheayy disappeared from the 
cut end of the stem for a distance 2-3 mm., and was most 
abundant towards the middle of the ienptl of the specimen. 
the presence of a considerable amount of starch were a 
necessary condition of attack by the boring insect, the treated 
specimen would probably meet the requirements, but it must be 
remembered that the removal of starch from a piece of stem 
immersed in water might be more rapid in a hot climate. 
The possibility that sugary contents might render the stem 
liable to attack is countenanced by the approximate absence of 
sugar in the soaked specimen. I'or comparison, a piece of small- 
stemmed bamboo (received from Mr. J. C. Fryer, Entomologist 
to the — of Agriculture), actually attacked by Dinoderus 
minutus, F. (the commonest boring beetle attacking dry bamboo- 
stems in India , ete.), was examined. Sugar in this specimen was 
relatively scanty, but aay. a sufficiently so to justify the 
rejection of sugar as a possible factor favouring attack. As far 
as nourishment is concerned, it may be supposed that certain kinds. 
of boring beetles can obtain sufficient from ae digestion of woody 
fibre, apart from the presence of sugar or star 
The matter has been discussed with Mr. ak who holds the 
opinion that scent is the special factor determining attack, that 
is to say that some odour, perceptible to the insect concerned, is 
the means by which it recognises the stem as bamboo, or as one 
of the plants which it attacks, and that if this scent is removed 
or sufficiently masked, the plant i is avoided. 
The effect of soaking i in water might be to remove some chemical 
compound on which the odour depends, or, if the matter is one of 
masking, this might be due to an added scent, either produced 
by decomposition of some component of the wood, or absorbed 
from the water, if, for instance, the wood is sunk in a pond 
containing decaying organic matter. 
The specimen from the pond had at first a very offensive smell, 
and still retains some of it, the smell being rather suggestive of 
organic sulphur-compounds. Though the mud of the pond may be 
responsible for this, it should be atta that a Bamboo (Bambusa 
arundinacea), is quoted as having a rather high sulphur-content 
in the ash of its leaves, 10-7 per cent. reckoned as SO,, as against, 
3-6, representing commoner values. 
Examination of sections of the same stem soaked in water at a 
temperature of 80° Fahr. for three month: 
An experiment was also made by soaking pieces of bamboo in 
the Victoria regia tank for three ‘months. This treatment was 
found to remove all the sugar present, but only a small pecan: 
of the starch. 
One may assume that, in the case of similar treatment in a hot 
climate, a stem, originally containing abundant starch, would 
