The present contribution is based on a study of a collection of preserved planktonic algae, made available to me by courtesy of professor PRESCOTT, Michigan State University The material contained 166 samples, collected' during the months April-December 1957, from Spring Lake in Ottawa County, Michigan . This collection was originally made for an experimental research of weed and algal control . The richness of the samples and variety of species seemed to offer a good opportunity for a detailed taxonomic study of the algal flora in this lake ; especially worthwhile since no similar survey has yet been made .
Spring Lake (see Map 1) is a fairly shallow, saucer type lake, possesing a narrow drainage basin . It has five major inlets, in which there is some water flowing at all times, and about a dozen minor inlets which become dry during the hot summer months . It drains into Grand River on South-West quarter. Spring Lake is about seven miles long and on the average 2 mile wide. It is estimated that it covers about 1000 acres or 1 .5 square miles . According to the Corps of Engineers, the major inlets set up a slow swirling of the water-the current flows South-West into Grand River . The bottom in some sections is deeply layered with organic slude, in others it is sandy. The higher aquatic plants form dense beds, composed of the species : Potamogeton crispus, P . richardsonii, Myriophyllum spp ., Nuphar variegatum, Scirpus sp ., Typha angustifolia and Lemna minor.
- The material was collected by Mr . WILLIAM REEs and Mr. EUGENE HANS- MANN.