19, 6 Merrill: New Species of Plants from Hainan 679 
characters. Our stenophyllous species grow on rocky banks 
and in the crevices of ledges in places subject to brief and sudden 
inundations by swiftly running water. In such habitats it is 
highly probable that the important cause of stenophylly is the 
fact that the various species, all shrubs and often small in 
size, have become adapted to the habitat from the effect of 
periodic brief inundations, as broad-leaved shrubs cannot long 
persist in such habitats. Gardenia stenophylla presents another 
example of the adaptation of a species to this peculiar habitat. 
It might better, perhaps, be considered merely as a variety of 
Gardenia augusta, its chief distinguishing character, the very 
narrow leaves, being due to its habitat. 
