Seed-coat anatomy is described in genera of Uvulariaceae of the Northern Hemis phere. The seed-coat anatomy of Uvulariaceae is varied, and based on cell shape, distribution and pattern of wall-thickenings and deposits among cell layers, five groups of taxa are recognized within the family : (1) Uvularia and Disporum, (2) Streptopus (including S. ovalis), (3) Clintonia, (4) Tricyrtis, and (5) Prosartes. These five groups show little significant similarity to the seed-coat of Convallariaceae (Asparagales). Rather, some of the groups show similarities to genera of Liliaceae or Trilliaceae. Prosartes has a thin-walled seed-coat significantly different from Disporum, in which Prosartes has been conventionally included. The seedcoat anatomy of Streptopus ovalis, which has been sometimes assigned in Disporum (as Disporum ovale), coincides well with that of Streptopus, rather than with that of Disporum. In the most part, these groups of taxa correspond to clades recognized in recent studies of rbcL sequences.
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