Front Matter
  I Introduction
  II Mendel's First Law - Segregation of the Genes
  III The Mechanism of Segregation
  IV Mendel's Second Law - The Independent Assortment of the Genes
  V The Mechanism of Assortment
  VI Linkage
  VII Crossing Over
  VIII Crossing Over and Chromosomes
  IX The Order of the Genes
  X Interference
  XI Limitation of the Linkage Groups
  XII Variation in Linkage
  XIII Variation in he number of Chromosomes and its Relation to the Totality of the Genes
  XIV Sex-chromosomes and Sex-linked Inheritance
  XV Parthenogenesis and Pure lines
  XVI The Embryological and Cytological Evidence that the Chromosomes are the Bearers of the Hereditary Units
  XVII Cytoplasmic Inheritance
  XVIII Maternal Inheritance
  XIX The Particulate Theory of Heredity and the Nature of the Gene
  XX Mutation