Justus Liebig and the Plant Physiologists Petra WernerFrederic L. Holmes OriginalPaper Pages: 421 - 441
From Haeckelian Monist to Anti-Haeckelian Vitalist: The Transformation of the Icelandic Naturalist Thorvaldur Thoroddsen (1855–1921) Steindór J. Erlingsson OriginalPaper Pages: 443 - 470
How Theories became Knowledge: Morgan's Chromosome Theory of Heredity in America and Britain Stephen G. Brush OriginalPaper Pages: 471 - 535
A Recapitulation of the Rise and Fall of the Cell Lineage Research Program: The Evolutionary-Developmental Relationship of Cleavage to Homology, Body Plans and Life History Robert Guralnick OriginalPaper Pages: 537 - 567
