Page:Proceedings of the Linnean Society of New South Wales, Volume 44.djvu/380

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{{rvh|352|WATER FROM THE ROOTS OF THE RED MALLEE.

the sap is least in the roots. This would be a most interesting subject for further observation. It will be noticed that, in the Red Mallee water, the proportions of soda and of chlorine are high relative to the other ingredients. In a series of analyses of Mallee soils published many years ago by the Agricultural Chemist of Victoria,[1] the amounts of soda and of chlorine vary within wide limits, the chlorine in one case rising as high as 0.20 per cent. of the soil. This corresponds to about 0.33 per cent. of sodium chloride, which is a high percentage for a soil, and is quite sufficient to account for the large proportion of soda and chlorine in the Mallee root-water.

Not all samples of sap obtained in the manner of the Mallee root-water are so dilute; Smith, for instance,[2] found enormously greater amounts of both mineral and organic solids in the sap from the timber of Grevillea robusta, while the juices of such plants as the sugar-cane and sugar-maple, carry large percentages of sugar, though not of mineral constituents; it must, however, be remembered that in the case of these latter plants the sweet sap is contained in special cells or vessels, and is not the ordinary circulating sap, but apparently functions as a food reserve. In the specimen of these roots exhibited by Mr. Fletcher, the cut ends showed a remarkable assemblage of open vascular tubes, reminding one strongly of a section of cane. From a consideration of the circumstances, I am inclined to think that the Mallee root-water may be a reserve supply for the use of the plant during droughty conditions stored in special vessels.

  1. Report Dept. of Agriculture, Victoria, 1875.
  2. Proc. Roy. Soc. N. S. Wales, 1896, p. 194.