9 QUEENSLAND AGRICULTURAL JOURNAL. {1 Jury, 1901, 
In proceeding to view the matter from a chemical as opposed to a physica] — 
standpoint, it may be stated that with regard to the contents of the cell itself, it must 
be confessed that our present state of knowledge is inadequate to admit of a 
pronouncement, being made with any accuracy as to the special modification of sap- 
composition that should be affected to meet the altered condition arising from the 
presence of sucrose in increasing amount. 
But in reviewing as far as practicable all the circumstances connected with the 
life of the plant, it would appear that what in this respect the higher sugar contenty 
necessitates, is, amongst other things, that the cell-sap should be endowed with ay 
increasing amount of lime. Now, with regard to this element whose presence is an 
essential to the maintenance of the healthy existence of all higher plant life, some of 
you are fully aware that, although in the case of the cane plant, great benefit in the 
direction of sugar yield is derived from its use, and that, moreover, it is taken up from 
the soil with avidity by it, yet the precise nature of the important part which it thug 
plays in its economy, considered as a living organism, is not yet ascertained. 
But to pass beyond the limits of demonstrated fact, and assuming, as a matter of 
high probability, that the oxalic and citric acids—derived from the sugar that occurs 
in the cell-sap, and especially so when this sugar is under the influence of lowly 
organisms of normal occurrence—that occur in the sugar-cane, do so in amounts 
proportionate to that in which the sugar itself (¢.e., formative sugar) is present. The 
maintenance of the health of the plant would demand that an increase of lime be 
forthcoming in order to prevent, by chemical union with them, these acids from 
interfering with the function of those enzymes whose action, as modern research 
indicates, is the basis of the exercise of one of the most fundamental functions of plant. 
life—viz., mefabolism—i.e., the systematic binding up or breaking down of food. 
material within its tissues by definite successive changes. 
The bearing of these propositions relating to the promotion of a tendency to 
disease that may attend our efforts at so-called sugar-cane improvement, will be 
apparent to many of you on your reflecting that when an outbreak of disease is 
experienced in our plantations it is the “ best’’ canes that usually suffer most; and to 
those few of you who, having—as has been the case with the writer—been privileged 
to examine the wild progenitors of some of our cultivated varieties, have observed 
that these are invariably healthy or free from disease. 
From these latter considerations it will appear that an inquiry into the origin of 
a sugar-cane disease may be something more than discovering an organism of © 
microscopical dimensions endowed with the faculty of producing a more or less serious 
alteration in the plants in whose tissues it has established itself, and demonstrating 
that this be so. In fact, it will be apparent that it may involve investigation far more 
rofound and complicated than is this, and one whose range has infinitely greater 
readth. They will also suggest that similarly the control of a malady affecting the 
sugar-cane may only be arrived at as the outcome of the expenditure of much time and 
labour in elaborate physical and chemical research. 
This important conclusion was foreed upon the writer when engaged in investigating 
the gumming in cane disease in the Bundaberg district some years ago, and finds expres- 
sion in the memoir embodying the results of the inquiry that was then undertaken. 
It was indeed the many difficult problems pertaining to the subject alluded to, 
and the impossibility of solving them until further facts regarding the life of the cane 
plant had been elucidated, that prompted the suggestion being made with which the 
report concluded, viz.—that a fully equipped and organised sugar experiment station be 
established. This suggestion, as you are aware, has happily borne fruit, and itaugurs 
well of its suecess from the point of view of a student of some of the obstacles to 
successful sugar-cane culture, that both in the personnel of its directorate and executive, 
it will provide exercise for the talents and ingenuity of one, at least, whose reputation 
as a physiological chemist has not only been widely admitted but justly earned. 
DISCUSSION. 
Mr. Tnos. Brynte (Cairns) stated that it was a fly, something like a 
mosquito, that bored the holes in sugar-cane and sucked the juice as described 
by Mr. Tryon, and not a fungns. 
Mr. F. W. Peek (Loganholme): The least we can do is to thank Mr, 
Tryon heartily for bringing his paper forward. We want a nomenclature 
committee for the naming of diseases as well as for the naming of varieties. 
We have had diseases of cane in my district, and Mr. Tryon came down, spent 
a few weeks amongst us, and thoroughly investigated them. He gave us their 
true names, properly explained their causes, and gave us remedies. ‘There are 
obstacles to cane culture, which Mr. Tryon did not touch upon, but upon which 
