Distributional patterns of Texas fresh-water fishes.

Distribution patterns of most fresh-water fishes in Texas closely resemble those of terrestrial organisms, though there are 3 exceptional groups: (1) those limited by stream divides, (2) those of marine and freshwater forms meeting in fresh waters near the coast, and (3) certain species of northeastern Texas (Austroripraian) whose ranges include outliners or extensions into other biotic provinces. It is concluded that the basic factors controlling distribution patterns of fishes are climatic and geological, these determining the properties of the water.