g TRANSACTIONS OF WAGNER 



THE VEGETATION OF THE HACKENSACK MARSH: A TYPICAL AMERICAN FEN 



land formations. The halms of this classic plant of Egypt reach a height of 

 over 3 meters. Associated with the papyrus is the Spanish reed {Arundo 

 Donax), the largest grass of Europe. 



REED MARSHES OF CENTRAL AND EASTERN EUROPE 

 Reed marshes are found in Saxony in several facies, one of which corre- 

 sponds with the fen formation of England. The reed marshes of the Car- 

 pathian region of Europe occur in the Hungarian Plain, along the streams, 

 and similar marshes exist in lUyria. 



The Plav of Rumania, according to Miss PalUs,* is a floating fen formed 

 almost entirely of living reed, Phragmites communis j8 flavescens. There are 

 three more or less well-marked growth stages of the reed grass, namely: the 

 open, the closed reed, and, in deep waters, Plav. The open reed marsh is the 

 stage at which the growth of the reed shoots is as yet sparse along the edge of 

 the lake or a stream, and the plants are fixed. Closed reed develops from open 

 reed marsh automatically, and in time becomes Plav. Much soil is held by 

 individual tussocks and by closely growing assemblages of tussocks. Plav, 

 when newly detached, does not differ from closed reed marsh, except in that 

 it floats. 



One plant, Typha angustata, competes successfully with the reed in the 

 delta of the Danube River, though it probably never supplants the reed 

 absolutely, but merely inhibits its growth for a time. In the delta, Phragmites 

 invades deeper water than Typha, hence it is only in shallow water that they 

 enter into competition. Cladium Mariscus also is found in the Danube fens. 



ASIATIC FENLAND 

 In central Asia, Phragmites communis is found about nearly all of the 

 rivers and lakes. The fens of eastern Turkestan, as at Kerija Darja, are the 

 refuge places for the wild birds and wild pigs of that country. About Lop 

 Nor, a lake in Chinese Turkestan, which is undergoing desiccation and is 

 only a few feet deep, there are unprecedented growths of this reed grass, 

 which, arching over the open channels of water, form tunnel-like passages for 

 the movement of the native boats. Reed marshes are found not uncommonly 

 in China (west of Shanghai), in Japan, about lakes Biwa and Chuzen. 



* Pallis, Marietta: Structure and History of Plav: The Floating Fen of the Delta of the 

 Danube. Joum. Linn. Soc, Botany, XLIII: 233-290, with plates and map. 



