TYPICAL SWAMP AREAS. 43 
The peat mosses which thrive so luxuriantly in poorly 
drained conditions are among the pioneer forms concerned 
in this process, while the cranberry (Vaccinium macrocar- 
AMARACK SWAMP 
Ko 
pon) quickly follows and soon forms a foothold for the 
leather leaf (Cassandra calyculata) and allied forms. 
On the land margin the tamaracks and spruces are closely 
