64 Keeble . — The Hanging Foliage of 
above experiments that thin delicate leaves of Amherstia 
nobilis, in which the chlorophyll-grains are developing, are, 
when exposed for a long time to the direct rays of the sun, 
in danger of injury to their green colouring-matter. There- 
fore, whether or not the hanging position is to be regarded 
as being a direct adaptation to protect the leaves from 
such injury, this vertical position, at least incidentally, ensures 
that such injury is reduced to a minimum. 
The second of the conclusions drawn by Stahl was next 
considered. This was, as already stated, that the hanging 
position does not signify a need for protection against ex- 
cessive transpiration, since, of leaves exposed to similar 
conditions of insolation, he finds that the young and tender 
wither less readily than the tough mature leaves. 
On first testing this, by means of branches of Amherstia 
nobilis cut under water and suspended with their cut ends 
under water, results similar to Stahl’s were obtained. The 
older leaves withered sooner. On repeating the experiment, 
however, it was found that, after a time, the young leaves 
had withered to such an extent that their leaflets were rolled 
up longitudinally and quite faded, whereas those of the green 
mature leaves were still perfectly fresh. The experiment was 
repeated. On this occasion one of the two branches cut at 
the same time bore large red leaves, the other red-brown and 
therefore older leaves. After some hours the younger leaves 
were quite withered, the older ones, on the other branch, 
were still fresh. In the above instances the stems were 
kept in water. In a third case the cut ends of the stems 
were not kept under water. Under these still more abnormal 
conditions the younger leafed branch again withered more 
rapidly than the older. 
In yet another case, two petioles, each bearing two leaflets, 
were put in the sun ; the leaflets of one were bright green, 
those of the other red-brown and consequently less mature. 
Other two similar sets, cut at the same time, were protected 
from the sun. After several hours, the young red-brown 
leaflets, which had been exposed to the sun, were found to be 
