XVI International Botanical Congess
Phyllanthoideae, a large subfamily of Euphorbiaceae, are investigated with respect to ovule and seed structure on the basis of 103 species of 48 genera in seven of eight constituent tribes. In Phyllanthoideae, the inner integument thin or thick, the outer integument mostly not vascularized but rarely vascularized, seeds lacking an aril, seed coat mostly ÒexotegmicÓ. Based on ovule and seed characters, a distinctness of Hymenocardieae, Lachnostylis, and Cleistanthus is discussed. On the basis of the shape of constituent cells of the exotegmen, the seed coat structure of the remainder of the subfamily is classified into five types and one subtype. In the light of the distribution pattern of those cell types, as well as of other ovule and seed characters, a uniformity and heterogeneity of each tribe is discussed.