A few definitions -- The relevance of systematics -- The importance and universality of classification -- Characters -- The anatomy of classification and the artificial approach -- Natural and phyletic approaches -- The phenetic approach -- The cladistic approach -- Evaluations of the three major approaches and explicit phyletics -- The taxonomic hierarchy -- The species -- The subspecies, variety, and form -- The genus -- The family and higher categories -- Morphology -- Anatomy -- Embryology -- Palynology -- Phytochemistry -- Cytology and cytogenetics -- Molecular biology -- Genetics and population genetics -- Reproductive biology -- Ecology -- The gathering and storage of data -- The presentation of data.