seldom occurs elsewhere, therefore useful in characterizing 

 the environmental conditions as a living label, cf. 

 Autochthonous. 



Indicator 



An organism, species, or community which indicates the 

 presence of certain environmental conditions, cf. Exclusive 

 species. 



Indifferent Species 



A species occurring in many different communities, a 

 Companion species (q. v.). See Fidelity. 



Indigen 



An indigenous species, cf. Cultigen. 



Indigenous 



Refers to an organism that is native, not introduced, in 

 an area. cf. Endemic, Exotic. 



Individual Ecology 



See Autecology, Idiobiology, Synecology. 



Infection 



The establishment of a Parasite upon an organism. 



Infest 



The establishment of an organism in numbers as para- 

 sites upon another plant or animal, e.g., aphids infesting 

 a rose bush. 



Infiltration 



The penetration of water into soil or other material, 

 cf. Percolation. 



Infiltration Capacity 



The maximum rate of Infiltration under a given set 

 of conditions. 



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