During the months of May and June of 1946, tremendous numbers of a brown hydra, tentatively identified by L. H. Hyman of the American Museum of Natural History, as Pelmatohydra olagactis, were found in the nursery lake known as Diamond Lake. Diamond Lake is located in sections 14 and 15 of Diamond Lake Twp., Dickinson County, Iowa. For the past fifteen years this shallow (maximum depth 6 feet), 160 acre lake has been used as a yellow pike perch, (Stizostedion vitreum vitreum, commonly known as walleye), nursery pond.
Proceedings of the Iowa Academy of Science
©1951 Iowa Academy of Science, Inc.
"Hydra in an Iowa Nursery Lake,"
Proceedings of the Iowa Academy of Science, 58(1), 501-505.
Available at: https://scholarworks.uni.edu/pias/vol58/iss1/65