Front Matter
p. 0
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Some Factors Affecting the Formation of Colonies in Gonium Pectorale
Graves, Lynn B., Jr.; Kostir, Wencel Jerome pp. 321-331
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The Limitations in Resolution and Discrimination in Brightness Differences for Light Amplifier Systems Using Contrast Enhancement
Gebel, Radames K. H. pp. 332-340
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Book Notice
p. 340
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Prehistoric Hopewell Meteorite Collecting : Context and Implications
Prufer, Olaf H. pp. 341-352
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Book Notices
p. 352
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Determinants of Cyclic Sedimentations in Pottsville Rocks Near Dundee, Ohio
Gray, Henry H. pp. 353-366
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A New Diplocardian Earthworm from Illinois (Oligochaeta: Megascolecidae)
Murchie, William R. pp. 367-371
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Book Notices
p. 371
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The American Upper Ordovician Standard. VI, The Covington Sequence at Maysville, Kentucky
Carpenter, James W.; Ory, Thomas R. pp. 372-378
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Book Notices
p. 378
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Index to Volume 61
pp. 379-380
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Back Matter
p. 999
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