246 CLIMAX AND SERE 



sume that shrub and tree top hiemal layer societies do not exist, as 

 birds and ants still occupy these levels during the winter (Smith- 

 Davidson, 1930), It is true also that many arthropod inhabitants of 

 herbs do not leave these until they have been broken down by frost 

 and snow. A few of them come up early in spring or even in warm 

 weather in winter and feed on the buds and shrubs before herbs have 

 appeared. 



The question of the relations of the plants and animals of the sub- 

 dominant communities to the chief dominants of a terrestrial biome, 

 to each other, and to the group as a whole is a difficult one. At the 

 outset of our discussion of this topic, it was thought that the entire 

 group of subordinate organisms could be treated together under the 

 term presociety, in the sense of a prevalent rather than a dominant or 

 controlling group. With further study of the literature and the com- 

 munities of waters, it became impracticable to recognize and separate 

 these two divisions of the biome, and the trend of investigation nat- 

 urally caused the term to be applied to animals only (Smith, 1928; 

 Shackleford, 1929; Bird, 1930), while in general the consideration of 

 plant layers has not concerned itself with the associated animals, or 

 the small and more subordinate lower plants. 



The problem of a natural or at least a logical classification of so- 

 cieties is connected with the need of modifying the concepts of family 

 and colony. In plant ecology, these have been employed for the first 

 two stages in succession, the family comprising all the individuals of 

 the pioneer species, and the colony, the group constituted when one or 

 more additional species invade the area. In zoology generally, family 

 and colony possess essentially the same significance, though the term 

 colony is more frequent and is usually restricted to invertebrates. In 

 the endeavor to render these terms both definite and distinctive, it is 

 proposed to employ family for the simplest grouping, in which the 

 individuals belong to the same species, whether plant or animal. In 

 the case of animals, they will have sprung from the same parents or 

 parent as a rule, though with plants this will have more frequent ex- 

 ceptions. The family will retain its character as the simplest initial 

 community, but it may appear in the climax as well as constitute the 

 first stage of a sere. In consequence, the colony will be limited to a 

 relatively small community of two or more species, either of plants, 

 plants and animals, or animals alone; in other respects, its position 

 and role in the biome will be much like those of the family. By con- 

 trast, the society has denoted a climax community of higher rank, 

 larger extent, and greater importance in terms of subdominants and 

 influents, but it is now proposed to employ it as a general term 



