Morphology of the Base of Seed Hairs of Gossypium II. Comparative Morphology

Abstract

The morphology of the base of the seed hair is examined for 33 taxa of the genus Gossypium L. The evidence generally corroborates established taxonomic views. In certain details, new interpretations are possible. Among the wild diploid species of the New World (the D genome), the observations presented support the classification of these species made by Maurer (1954) and fail to support groupings made by others. The relation of ploidy level to cell size is discussed, insofar as it involves seed hairs. The differentiation between fuzz and fiber is found to be greater in the diploid cultivated species of the Old World than in the tetraploid species of the New World. The bearing of these observations on the origin of the tetraploids and the domestication of the cultigens is discussed.