THE CHARTOGRAPHERS OF THE STATION 



183 



and aits as separate the channels of a water-stream. On trails where, as 

 sometimes happens, mobs are always driven out in one direction and 

 always return by another route, these aits and islands of bracken 

 permanently maintain a somewhat deltoid shape. On the main stock- 

 route, along which an ovine current flows like a tide both toward the 

 wool-shed and away from it, deltoids become lanceolate or sharply ovoid, 

 like the raised " refuges " of city thoroughfares. 



The final stage of a stock-route might well puzzle any man who has 

 not followed each step in its strange metamorphosis. Nothing would 

 appear more unlikely than that a drove-road through bracken should 

 develop sometimes into a single sinuous line of shrubbery, sometimes 



Sheep driven through dense fern. 



Single hedge line. 



into a grassed space bounded by high hedges on either side. It has 

 nevertheless happened, single or double serpentine ribbons of scrub 

 have moulded themselves to the shape and sinuosities of stock-tracks 

 as the roots of a parasite grow to the form of their host. 



The stages through which every paddock of Tutira has passed in its 

 alteration from tutu and fern to grass are known to the reader. He will 

 recollect that bracken and scrub, in early days, grew nearly everywhere 

 tall and rank enough to shut out sunlight from the soil ; that in the 

 'nineties the effect of stocking began to show itself in their weakened 

 growth ; he will remember, too, that from time to time the country used 

 to be swept bare by extensive fires. Keeping these facts in mind, we 



