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Roanoke in North Carolina and the Great Pee Dee in South Caro- 

 lina, although I have no doubt that other rivers under suitable 

 conditions would furnish equally good examples. These condi- 

 tions seem to be that there shall be a variable water content so 

 that the autumnal fall of leaves will have a chance to form a thick 

 carpet on the low mud-banks or exposed sand-bars of the 



Figure 2. A stranded leaf-raft, Great Pee Dee River, South Carolina. 



meandering stream, where they accumulate for weeks. With the 

 return of high water the following spring or possibly not until 

 summer, although the largest rafts are to be seen in the spring, 

 they float away seaward. They are remarkably uniform in their 

 character and contain but few sticks or foreign matter, the bulk 

 of the material consisting of the matted leaves of the sycamore 

 {Platamis), elm [Ulmus), birch {Betiila), and the willow and chest- 

 nut oaks, with a considerable admixture of other species, includ- 

 ing the more rapidly decaying leaves of the sweet gum and other 

 trees that haunt the river banks. 



These rafts furnish a most perfect illustration of one of the 



