ENALUS ACOROIDES. 
283 
impossible that they are dissolved in the water long before 
the next low water period. As a comparison I have made 
an experiment : if a seed with long hairs, for instance that of 
a Strobilanthes, is dropped into a jar of boiled water which 
contains no air, the air bubbles which are always present 
between the hairs require 3-8 hours to be dissolved. Of 
course, this result cannot be regarded as absolutely decisive 
as the conditions are not the same, but it makes it never¬ 
theless probable that air bubbles, possibly a hindrance, 
may be dissolved during the time the flowers are sub¬ 
merged. 
It is remarkable that the discharge of the male flowers 
also occurs somewhat exclusively during low water, as I had 
frequently occasion to observe in Jaffna. My attention was 
called to this fact in a singular way. One morning during low 
water I had observed the loosening and catching of the male 
flowers, and had also preserved some of them for investigation. 
In the meantime, wanting more material, I visited the same 
place later on in the same day, but in spite of eager search 
and long waiting I could not see any male flowers at all. I 
did not then understand the reason. Next morning when it 
was low water again I made a new attempt at the same place, 
and then with better success. Just as during low water the 
previous day, male flowers in great numbers floated up and 
swam about as before. Afterwards during my stay in Jaffna 
I repeatedly had the opportunity to notice the same thing, 
viz., that it is during low water that the loosening of the 
male flowers take place. 
This phenomenon may easily be explained by the 
differences in the pressure of the water during high and 
low water. The male flowers are like balloons when closed. 
When ripe they are filled with gases, and the sudden 
recurving of the sepals and petals may apparently be due 
to the pressure of the gas bubbles on reaching the air. As 
the perianth, within certain limits, can easily be more or 
less pressed together, the explanation of this periodical 
