( 315 ) 
Already on the evening of the same day, clear droplets could be 
«>en at the apex and the teeth of the outermost leaves, and at the 
apices of the next pair of leaves, while the space between each parr 
of young leaves was filled with water. 
The apex and the teeth of the budleaflets differ especially in 
anatomical structure from the rest of the leaf in having larger epi¬ 
dermal and subepidermql cells, which have a denser contents and 
contain stomata at an early age. 
Reinke is of the opinion that these cells secrete mucilage in the 
younger stages of the bud, but I have not been able to observe this. 
I consider that in this case the secretion of water is not preceded 
by that of mucilage, but that the glandcells secrete water from 
the outset. 
The surface of the leaf is further covered with numerous uni¬ 
cellular long, pointed hairs, which are laid down very early; their 
rounded base is afterwards surrounded by prolonged epidermal cells. 
From these pointed hairs with rounded base the water is doubt¬ 
less derived which under the bell-jar fills the space between each 
pair of leaves; they are therefore true waterglands, not glands 
which formerly secreted mucilage (balsam or resin). 
A month later when the 4 or 5 outermost pairs of budleaves 
were fully grown, the experiment was repeated. The adult leaves 
had now lost their power of secreting 
and there now only 
appeared waterdrops on the two pairs of small immature leaves 
and on a pair of leaves of the bud. 
Hydrangea pubescens. 
On the 1 st of May a cut branch was submitted to the experiment 
in a glass of water‘under a moist glass bell-jar. The outermost pair 
of leaves of the buds was not yet fully grown, but nevertheless 
the leaves had already taken up a horizontal position. The following 
pair of leaves was still erect, but the leaf-margins which at an 
earlier stage were closely applied, began already to separate; the 
other leaves still formed a completely closed bud. 
The leaf of Hydrangea pubescens terminates in a long apex and 
bears on its margin a large number of long narrow teeth, which 
point outwards in the upper half of the young leaf and which in 
the lower half are more or less directed backwards. 
In each tooth a vein terminates and above this there are one or 
more waterpores. The young leaves are further covered above and 
below with long unicellular hairs; those of the upper surface are 
broad, rounded above and have very thin walls, those of the lower 
