When samples of algae taken from bodies of water in the various parts of the State of Kentucky were being examined it was noticed that some species were common in one or a few of the soil regions and were entirely lacking or extremely rare in others while other forms were common throughout the state. There are, in reality, ten rather distinct soil regions in Kentucky, but since five contain most of the algae only that number will be considered when making comparisons. In this discussion it is assumed that the nature of the water depends upon the type of soil present and that a chemical analysis of the soil gives some evidence concerning the qualities of the water.