On the Local Distribution of Certain Illinois Fishes:

Abstract

This paper is thus to be taken as a contribution to an answer to the following questions: What Illinois fishes are habitually found in each others' society,and what is the relative frequency of their associations? How are Illinois fishes grouped and distributed according to location and situation, and in each ecological assemblage so formed what is the proportionate representation of its various constituent species? How far are the two classes of data^ those of associative affiliation and of ecological relationship, comparable, and to what extent may the one be used to explain the other?