THE NATURE AND REACTION OF WATER FROM 
HYDATHODES 
J. K. WiILson 
In the process of growth and development, plants lose various parts 
of their structure. Root hairs are, relatively speaking, of short duration, 
and root-cap cells are gradually sloughed off; while pollen and other floral 
parts are soon lost. In addition to this loss of organic material, the 
plants return to the soil, by a gradual passing downward and outward 
through the root system, various inorganic and organic materials. These 
materials may be lost also through special organs, such as the nectaries 
or the hydathodes, the materials either falling off or being washed away 
by rain or dew. 
In studying the effect that plants have on the growth of bacteria in 
soil, it became desirable, in order to throw light on the results that were 
being obtained, to make a study of the presence of certain materials in 
the exudate water of maize, oats, and timothy. This paper gives the 
results of the findings from this study, in so far.as they bear on the broader 
investigation. i 
PREVIOUS STUDIES 
An investigation somewhat similar to this was pursued by Berthelot 
and reported by Duchartre (1859). Four hundred cubic centimeters 
of guttation water was collected from Colocasia and evaporated to dry- 
ness. The residue contained potassium chloride, calcium carbonate, 
and a mucilaginous material. The last-named was completely soluble 
in all concentrations and produced a froth when boiled. When the dry 
residue was heated, it carbonized. It is concluded, however, that only 
the merest traces of organic and inorganic materials were found in this 
exudate, and that the concentration was about equal to that of distilled 
water. . 
Marloth (1887), in Egypt, collected the salts from the leaves and stems 
of Tamarix. The dry salts consisted of CaCO; 51.9 per cent, MgSO.,H.O 
12 per cent, MgCl, 4.7 per cent, MgHPO, 3.2 per cent, NaCl 5.5 per cent, 
NaNO; 17.2 per cent, and Na,COs; 3.8 per cent. 
Lepeschkin (1906) analyzed water from the secreting cells of a number 
of plants. In addition to a considerable number of inorganic substances, 
certain organic compounds were found. Glucose was secreted from 
Vicia sativa and Polypodium aureum, while basic oxalic acid was found 
in the water from Lathyrus odoratus. 
The forms of nitrogen in plants were studied by Klein (1913). Guttation 
water was collected and examined, diphenylamine and nitron being 
used as reagents. Klein concluded that nitrates were not found in the 
exudate water from Splitgerbera biloba, Fuchsia sp., Nicotiana silvestris, 
Tradescantia viridis, Tolmiaea Menziesii, and Zea Mays seven weeks old, 
but were present in that from Zea Mays seedlings five days old. Also, 
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