204 OXYLOPHYTES SECT, vi 



Distinctions between low-moor and high-moor : * 



1. Low-moor arises on a surface that is covered with water it is 

 infra-aquatic in origin. 



High-moor arises in water or on moist soil or even above water, from 

 which it emerges and rises, becoming dependent solely upon atmospheric 

 water it is supra-aquatic. 



2. Low-moor has a flat surface (either horizontal or inclined). 

 High-moor has a convex surface like a watch-glass. 



3. Low-moor is produced particularly by grass-like plants, including 

 Cyperaceae, Gramineae, and Juncus, also by Hypneae. 



High-moor owes its origin particularly to bog-mosses, Sphagnum 

 and others, and includes many Ericaceae. 



4. Low-moor water is calcareous. 

 High-moor water contains little or no lime. 



5. Low-moor forms black amorphous peat from its vegetable remains, 

 which are so disintegrated as to be scarcely recognizable. 



High-moor preserves its plant-remains in a higher degree. 



6. Low-moor peat is heavy and rich in mineral bodies (with 10-30 

 per cent, of ash). 



High-moor peat is light in weight and poor in mineral matter (with 

 about 5 per cent, of ash). 



7. Low-moor peat is usually close in texture, and when wet is conse- 

 quently ' greasy ', and conducts water badly, so that it may be quite dry 

 on top but wet and ' greasy ' at a slight depth (it is almost useless for 

 horticultural purposes). 



High-moor peat is almost throughout uniformly moist or dry because it 

 conducts water well, and is rich in air (it is frequently used by gardeners). 



8. Low-moor soil is very rich in food-material for plants, so that it 

 entertains mainly ' eutrophic ' plants, 2 which are adapted to live at the 

 expense of nutritive solutions present in the soil : fungal life is scanty. 



High-moor soil, on the contrary, is very poor in nutriment, for instance, 

 in nitrogen, so that the vegetation consists of ' oligotrophic ' plants : 

 fungal life is very abundant, so that there is a keen struggle for the 

 nutritive salts. 3 Probably to this is due the occurrence here of plants 

 that obtain nitrogen by means of their leaves carnivorous plants. 



9. On low-moor mycorhiza and carnivorous plants are rare. 



On high-moor mycorhiza and carnivorous plants are common : all 

 the Ericaceae, as well as Empetrum, Betula, and others have mycorhiza ; 3 

 while, for instance, Drosera, Dionaea, Sarracenia, Darlingtonia, Cepha- 

 lotus are inhabitants of high-moor. 



GEOGRAPHICAL DISTRIBUTION OF HIGH-MOOR 



Even more than low-moor is high-moor governed by climatic conditions, 

 because it is dependent solely upon atmospheric precipitations and not 

 upon water in the soil. Consequently the distribution of high-moor is 

 more restricted than that of moors as a whole. 



Within the tropics the production of peat is almost confined to 



1 Fruh und Schroter, 1904, pp. 12-15. See also Weber, 1907, and his other 

 papers cited in the Bibliography. 



2 C. Weber, 1 907, and his other papers cited in the Bibliography. 3 Stahl, 1 900. 



