150 PLANT LIFE 
The epiphytes form a large class, and they 
include many of the humbler members of 
the vegetable kingdom as well as a consider- 
able number drawn from the highest ranks of 
flowering plants. 
They exhibit all grades of adaptedness for 
the acquisition and storage of water. At the 
lowest end we find some of the simpler forms, 
especially amongst the algze and mosses, 
which will stand complete dessication. But 
there are other species of mosses, and especially 
of the nearly related family of liverworts, 
which have advanced far beyond the attitude of 
mere tolerance, and not only exhibit adapta- 
tion for rapid water absorption, but also 
possess means of storing it during a time of 
plenty. In some liverworts tuberous bodies 
are formed, and during the dry season these 
alone persist, to break out into growth as 
soon as the rains commence. In the leafy 
forms it often happens that some or all of 
the leaves are modified so as to form bottle- 
like receptacles (Frullania, Physiotium, etc.) 
for water. 
It is amongst the ferns and flowering plants, 
however, that we find the greatest diversity, 
and perhaps we might add perfection, in the 
adaptations to solve the problems connected 
with a precarious and intermittent water 
supply. 
It is true that the majority of the highly 
specialised epiphytes are more or less restricted 
to regions of large and fairly frequent rainfall, 
