Freshwater Sponge Spicule
This is from a core sample collected in Lake Washington, Seattle, Washington.
Transmitted Brightfield Illumination
Significance in the Environment:
Pennak, Robert W., FRESH-WATER INVERTEBRATES OF THE UNITED STATES, 2nd Ed., Wiley Interscience, pp. 80-98, 1978.
(Identification Key for Freshwater Sponge Spicules)
Wilding, L.P. and L. R. Drees, "Distribution and implications of sponge spicules in surficial deposits in Ohio",
THE OHIO JOURNAL OF SCIENCE, vol. 68, no. 2, pp. 92-99, 1968.
(Transport Mechanisms for Spicules far from Lakes)
Kratz, T.K., K.E. Webster, C.J. Bowser, J.J. Magnuson, and B.J. Benson, "The influence of landscape position on lakes in northern
Wisconsin", FRESHWATER BIOLOGY, vol. 37, pp209-217, 1997.
(Environmental Factors Favoring Production of Sponge Spicules)