New evidence of reproductive organs of <Emphasis Type="Italic">Glossopteris</Emphasis> based on permineralized fossils from Queensland,Australia. I. Ovulate organ <Emphasis Type="Italic">Homevaleia</Emphasis> gen. nov.

This study describes Homevaleia gouldii H. Nishida, Pigg, Kudo et Rigby gen. et sp. nov., an ovule-bearing glossopterid organ, based on a combination of recently collected permineralized specimens from the Late Permian Homevale Station locality in the Bowen Basin of Queensland, Australia, and on previously studied material from the 1977 Gould and Delevoryas study. Homevaleia, which resembles the compression–impression genus Dictyopteridium, is an inrolled megasporophyll with a distinct keel that bears numerous (over 70) stalked ovules on its adaxial surface. Ovules are small, oval, with an elaborate mesh-like structure that is developed from the outermost integumentary layers. Specimens interpreted as representing different developmental stages show there is an apparent interrelationship between megagametophyte development and the opening of the surrounding fertile structure for pollination. Together, new information provided by this material enables better understanding of glossopterid reproductive structure and its function in one distinctive form.     

Paleoactaea gen. nov. (Ranunculaceae) fruits from the Paleogene of North Dakota and the London Clay

Paleoactea nagelii Pigg & DeVore gen. et sp. nov. is described for a small, ovoid ranunculaceous fossil fruit from the Late Paleocene Almont and Beicegel Creek floras of North Dakota, USA. Fruits are 5-7 mm wide, 4.5-6 mm high, 10-13 mm long, and bilaterally symmetrical, containing 10-17 seeds attached on the upper margin in 2-3 rows. A distinctive honeycomb pattern is formed where adjacent seeds with prominent palisade outer cell layers abut. Seeds are flattened, ovoid, and triangular. To the inside of the palisade cells, the seed coat has a region of isodiametric cells that become more tangentially elongate toward the center. The embryo cavity is replaced by an opaline cast. This fruit bears a striking resemblance to extant Actaea, the baneberry (Ranunculaceae), an herbaceous spring wildflower of North Temperate regions. A second species, Paleoactaea bowerbanki (Reid & Chandler) Pigg & DeVore nov. comb., is recognized from the Early Eocene London Clay flora, based on a single fruit. This fruit shares most of the organization and structure of P. nagelii but is larger and has a thicker pericarp. This study documents a rare Paleocene occurrence of a member of the buttercup family, a family that is today primarily herbaceous, and demonstrates a North Atlantic connection for an Actaea-like genus in the Paleogene.