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PLANT SOCIOLOGY 



Europe. From his work we have taken the following table, illustrating 

 the actual procedure in establishing alliances : 



Table 40. — Alliance of the Nanocypebion Flavescentis 



Just as the association is designated by attaching the suffix -etum 

 to the stem of the genus name, so an alliance is designated by attaching 

 the suffix -ion. We speak of the Ammophilion of the Mediterranean 

 and Atlantic sand dunes, of a Rhodoreto-Vaccinion of the Alps, etc. 

 Where necessary, a species name in the genitive may be added to the 

 genus name, as Caricion curvulae. As key word we may use the 

 designating species of one of the most important associations ; or a new 

 compound name (Nanocyperion, Magnocaricion) may be chosen. 

 Occasionally, reference is made to the dominant life form, as in the 

 Thero-Brachypodion of the Mediterranean region; or the geographic 

 limits of the alHance may be utilized, e.g., Potamion-eurosibiricum. 



Order. — The "order" stands above the alliance. In pursuance of 

 the floristic principle of classification, orders of communities are 

 primarily circumscribed by their component associations and alliances. 

 Each order has its special characteristic species. The individual orders 

 are also ecologically characterized. To designate an order, the com- 

 pound suffix -etalia is added to the root of the name of one of the most 

 important associations, as in Molinietalia. 



One of the best known orders of Central Europe, the subalpine 

 Caricetalia curvulae of moderately to strongly acid, xeric or mesic soils, 

 is divided as follows: 



