34 
THE FERN WORLD 
Ferns. The conditions which favour their early existence 
are maintained. The soil is annually enriched by additional 
deposits of leaf-mould, and, the moisture and shelter con- 
tinuing, the Ferns grow to maturity, and then spread their 
myriad atoms of reproduction, which, wafted to other rocky 
holes, moist banks, and old, moist forks of trees, soon fill the 
forest with graceful ferny forms, covering sloping banks, 
waving from the crowns of pollard trunks, and draping rock 
and river with their feathery tresses. 
Or take the case of a stream which flows rapidly through 
a mountain gorge, or along the boulder-strewn bed of a 
valley. Vegetation of large growth — trees or giant shrubs 
— will follow the course of such a stream, for its moist 
channel is favourable to the development of vegetable life. 
The stream brings moisture ; the trees or other growths bring 
shelter ; the force of the current makes and maintains holes 
and fissures in its earthy or rocky bed. These are filled with 
leaf-mould from dropping leaves, and with sand and fibres 
from the carrying stream. Then Nature begins her work, 
and plants her small growths of moss, lichen, and Fern on 
the dark moist surfaces of earth or rock. The process of 
dwarf-forestry commences, and slowly and surely the whole 
ground-plan is draped with a mantle of living green. 
Chance, perhaps, has thrown together in mid-stream some 
shapeless masses of rock : the water brings down a con- 
tingent of broken branches torn from their parent stems by 
the force of high winds, or fallen under the process of 
natural decay. The jutting masses of stone arrest the 
woody fragments, and these in their turn catch the passing- 
whirl of stream-borne leaves, and dam the earthy substances 
washed down from the banks of the stream above. A 
process of accumulation commences. The mass thickens and 
strengthens, and some bold plant starts up from its centre. 
Others follow, and their matted roots consolidate the sub- 
