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THE AMERICAN BOTANIST 



a marsh is formed by filling up the shalloAv water at the mouth 

 of a river by material brought down by the stream in times 

 of flood, the English call it a fen. The lands in the lower 

 Mississippi valley might properly be called fens. The fen may 

 or may not contain peat but it always differs from the moor in 

 this important particular : the soil is always alkaline and not 

 acid. It therefore supports a very different set of plants from 

 those of the moor, among which, coarse grasses, sedges, cat- 

 tails and the like may be found. 



The heath is a dry and sterile region that nevertheless 

 partakes somewhat oi the character of the moor. Like the 

 moor it has a peaty soil with an acid reaction which explains 

 why some of the common plants of the moor may be found on 

 the heath as well. Though heaths are characteristic of dry 

 regions, they seldom develop in limestone countries and when 

 they do, it is always in situations where the soil lacks lime. 



The heath has long been known by the name it bears ; in 

 fact, there must have been heaths before there were heathen. 

 The heathen, however, are not alone in deriving their name 

 from the heath : the characteristic plants of the region are also 

 heathen or, rather, heaths, which is merely a different form of 

 the plural. Originally, any plant which grew on a heath was 

 called by this name, but in later days the term has been reserved 

 for the members of a great plant family known otherwise as 

 the Ericaceae. In Europe, the principal heath plant is the ling 

 or heather (Calluna vulgaris), thoug'h with it there are usually 

 associated two species of Erica which are also called heather on 

 occasion. TwO' heaths related to our blueberry — Vaccinium 

 myrtillus, called bilberry or whortleberry in Britain and V ac- 

 ciniiim vitis-idaea, the cowberry or lignon berry — are also 

 usually abundant. The fruit of the latter is regularly exported 

 tO' the United States. 



In South Africa as well as in our own part of the world, the 

 drier regions are characterized by an abundance of heathworts. 



