THE SMALLER SOCIAL UNITS 23 



comparisons between the various bits of vegetation. Pieces of vegeta- 

 tion with similar combinations of species are united into abstract types. 

 These types are the "associations, " the separate pieces being called the 

 individuals or examples of the association or more simply the "stands. " 



Individual Association or Stand. — The more or less similar bits of 

 vegetation or "stands" found in nature are the concrete realities with 

 which the plant sociologist has to do. An association usually includes 

 many spatially separated stands. They correspond in a general way 

 to the individual plants in taxonomy, although the anthropocentric 

 assumption of individuality applies to them in a lesser degree than to 

 individuals of a species. 



The larger the number of stands investigated the more truthful 

 will be the resulting picture of the association. From the more or less 

 perfect agreement in the composition of these stands comes the greater 

 or lesser uniformity of the association and the range of its variation. 



The concept of the association includes a true reality, namely, the 

 characters common to the individuals of the associations. The associ- 

 ation as such, however, is, hke all systematic categories, a group con- 

 cept, intended to deepen and organize our knowledge of vegetation. 



Alechin (1925) regards this group concept itself as an indivisible 

 unit and likens the stands to the pieces of a cut apple. ^ He overlooks 

 the fact that the piece of apple can no more regenerate itself than can a 

 quartered ox, whereas each stand arises independently of the rest 

 of the association and can continue to develop and reproduce itself 

 independently. 



Each stand has in itself a distinct individuality, with its own life 

 history, and embodies in itself the distinctive marks of the association. 

 The practical and theoretical value of the association concept depends 

 upon the greater or lesser external and internal resemblances of the 

 several individuals of the association. An important phase of the 

 study of vegetation is the distinguishing of these resemblances. This 

 leads to sharper individualizing and dehmiting of the association from 

 the floristic, ecologic, genetic, and geographic viewpoints. 



The stand embodies the association as one house embodies the 

 concept house. This prolonged discussion seems to be necessary for a 

 better understanding of many sociological treatises. It is to be hoped 

 that the proposal of Nichols (1923) will continue to gain ground and 

 that the word "association" will be used both in a concrete (an associa- 



1 The same error is made by Vierhapper (Verh. Zool.-Bot. Ges., Wien, 74-75: 

 1924-1925), who likens the Einzelbestand to a granite block. On this account 

 his proposal of the Assoziationselement cannot hold. 



