VICTOR E. SHELFORD. 



IV. Thicket or Forest Margin Formations of the Savanna and 

 Forest Climate. 



A. Wet Ground Thicket Associations. (Lower strata 



occasionally submerged.) 



1. River Deposit (Silt) or Stream Margin Thicket 



Sub-formations. 1 (First stage in the develop- 

 ment of Flood Plain Forest.) 



2. Marsh and Pond Margin Thicket Sub-formation. 



(First association in the development of forest 

 in marshes.) 



3. Candle-head or Moist Forest Margin or Thicket 



Sub-formation of the Savanna and Deciduous 

 Forest Climates. 



B. Straussia longipennis of High Forest Margin Associ- 



ations of the Savanna Climate. (A climatic associ- 

 ation of considerable permanency.) 

 V. Forest Communities of the Deciduous Forest Climate. 



A. Formations on Sand in the Deciduous Forest Climate 



or Province. 



1. Cicindela lepida or Cottonwood Association. 



2. Cicindela Lecontei or the Pine Association. 



3. Ant Lion or Black Oak Association. 



B. Climatic Forest Formation of the Deciduous Forest 



Climate. 



1. Blackoak-Redoak Association. 



2. Cicindela sexguttata or Redoak-Hickory Associa- 



tion, (i and 2 were treated together in the pre- 

 ceding paper and in the discussion above but 

 may readily be separated.) 



3. Rana sylvatica or Beech-Maple Association. 

 Each division made here is based upon observations on the 



ecology of the animals constituting it. Marked differences in 



1 The term association is applied mainly to stages in the development of climatic 

 and of old topography formations; subformation (Warning), to communities com- 

 parably different physiologically but not clearly genetically related, or to associa- 

 tions when no genetic relationships are implied. Thus here in a classification 

 intended to be primarily physiological, the stream margin thicket is placed among 

 the thicket formations while in a purely genetic classification as shown in the chief 

 features of arrangement in Fig. n it would be termed a stage or association in 

 flood plain forest development. 



