The effect of hydrogen-ion concentration upon the fixation image of various salts of chromium

Amines in cytological fixing fluids

Aldehydes as cytological fixatives

The Inheritance of Acquired Characters and the Provisional Hypothesis of Pangenesis

The Involuntary Destruction of Science in the USSR

Soil Exhaustion, the Territorial Limitation of Slavery, and the Civil War

News

The Death of Gaius Plinius Secundus (23-79 A.D.)

The Theory of Concentric Spheres: Edmund Halley, Cotton Mather, & John Cleves Symmes

Gregor Mendel & His Precursors

Benjamin Franklin, Thomas Malthus and the United States Census

Development of Normal and Divergent Plastid Types in Zea Mays

The Plant Vacuole