Fiji. 4. 



Abandoned bends at high levels show that the stream has been uieau- 

 dering for a long period. The fact that it no longer overflows its valley 

 floor, but only the channel floor, means that it is slightly intrenched, is 

 making a new flood plain at a lower level, as the cross profile shows 

 (Fig. 2), and leaving its former flood plain as a terrace. In Intrenched 

 meanders cut-offs are rare, because they occur only where a neck is cut 

 through by lateral erosion. The cut-offs of Normal brook are made in 

 this way and not by overflow across a neck. In such cases the meander 

 belt has no self-limiting width, but is restrained only by the bluffs. In 

 Normal brook the width of the belt is about thirty times the width of the 

 low water stream and not more than five times the average width of the 

 high water channel. The present base level for the brook is the surface 

 of the gravel terrace in the Wabash valley. The brook once emptied di- 

 rectly into the river when it stood at a level ten or flfteen feet above the 

 terrace. Therefore the brook has been subjected in post-glacial times to 

 a fall of ba.se level of that amount. Meanders acquired during a condition 

 of higher base level and gentler slope may have been inherited and mod- 

 erately intrenched by the pre.sent stream. 



