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Indian Forest Records, 
[Vol. VIII 
passing through the leaves was probably not deprived of its 
oxygen by soil organisms and, the leaves being protected 
from rapid decay, decomposition products could not 
accumulate. 
(6) Point (2) above indicates that sal seeds are particularly liable 
to damage by drought. This, however, does not imply 
that submerging the seeds in water is likely to be a good 
thing. To test this point, in 1918, four large glazed pots 
were filled with Song river sand, and 2 of the pots were 
placed under the shade of trees and 2 in the open. On June 
24th, 1918, 20 sal seeds were placed on the surface of the sand 
in each pot. Each pot was then filled with clean tap water 
(the water being sufficient to entirely cover the seeds), 
the drainage holes at the base of the pots being closed by 
corks. As the water diminished by evaporation, more water 
was added so that the seeds were kept constantly submerged. 
Under these conditions every one of the 80 seeds sown failed 
to germinate, whereas 25 per cent, of the seed sown similarly 
on the same sand in adjacent pots in the shade, on the same 
date, and which were merely lightly watered as usual, 
without being submerged, germinated successfully. 
It is possible that the injury caused by submerging the seeds is due 
to a temperature effect and that a certain amount of evapora¬ 
tion is necessary from seeds exposed to a high temperature 
in order to keep the temperature of the seeds below the 
lethal maximum. The air temperature in Dehra Dun, 
in July 1918, was unusually high. 
(7) Points (1), (2), and (3) above clearly indicate that in this experi 
ment dead leaves have had a two-fold injurious action, 
viz .:— 
(а) a drought action resulting from the separation of the seeds 
from the soil surface by a dry layer of leaves. 
(б) a mechanical action caused by the resistance of the tough 
leaves to the passage of the radicle downwards, the latter 
being forced to move horizontally between the leaves, 
instead of vertically downwards. 
(8) Points (1), (2) and (4) indicate that sal seed is especially liable 
to damage from drought and a high temperature. It is 
well known that sal seed is difficult to keep and that, as a 
rule, it tends to lose its vitality quickly. It is also known 
that, unless early and plentiful showers are obtained shortly 
after the fall of the seeds, the great majority of the seeds in 
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