prepare the way for other communities which succeed them.. 

 For these Clements proposes other terms, viz., Associes„ 

 Consocies, and Socies, these being the developmental or serai 

 equivalents of Association, Consociation and Society. Further 

 a Colony is a pioneer or initial community of two or more 

 species, and a Family according to Clements, in the ecological 

 sense is a group of individuals belonging to a single species, 

 which usually soon becomes converted into a colony. This, 

 last term is likely to lead to confusion, since it is also used in 

 another sense, so it will not probably be generalh r adopted. 



Instead of using the term "succession" both in a concrete 

 and in an abstract sense, Clements uses the word Sere as a term 

 for a definite single or unit plant succession. It comprises the- 

 development of a formation from the appearance of the first 

 pioneers through all the stages to the climax. The various, 

 successions are further divided into Primary and Secondary 

 with the corresponding terms Prisere and Sub-sere. Priseres 

 are the main regional successions, and their analysis is not 

 always easy. Sub-seres are confined to bare areas due to super- 

 ficial disturbance, and are largely due to man's interference. 

 For example: the succession from abandoned cultivated land 

 back to grassveld is a Sub-sere, as is also regeneration in a 

 burnt-out forest. The Sub-seres are much more numerous and' 

 more easily investigated than the Priseres. 



Priseres and Sub-seres are further sub-divided according 

 to the nature of the extreme area which is colonised by the- 

 initial or pioneer communities, into (1) a Hydrosere which 

 begins in wet places such as Yleis, and (2) a Xerosere which 

 begins in dry places. There are other proposed terms, viz., 

 Haloserc for salt water, O.rysere for acid water, and the- 

 Xerosere may be divided into JJthosere for rock surfaces, and 

 Psammosere for sandv areas. 



