Fossil plants; a text-book for students of botany and geology, by A. C. Seward.

Abstract

Cladoxylon mirabile ; G. duhium ; C. taeniatum ; Syncardia pusilla 202 460. Cladoxylon Kidstoni ; C. mirabile 461. Volkelia refracta 209 462.

Resolving the systematic and phylogenetic position of isolated ovules: a case study on a new genus from the Permian of China

“…In terms of its gross morphology, given 180° rotational symmetry, a narrow micropyle and vascularization of both the nucellus and integument, the features of the ovule are consistent with those of cardiocarpalean‐type ovules (Cardiocarpales sensu Seward, 1917; see Hilton et al ., 2003). However, the pattern of vascularization, specifically the well‐developed integumentary bundles and nucellar bundles arising from a pad at the base of the nucellus are more typical of some lagenostomalean and trigonocarpalean‐type ovules, but in their precise form are distinct from other recognized ovules.…”

“…Stevens, 2006b), has been documented. Traditional serial acetate peels revealed exquisite cellular detail in the new material and showed similarities with several different ovule genera from contrasting traditional Palaeozoic ovule groupings of cardiocarpalean, trigonocarpalean and lagenostomalean ovules ( sensu Seward, 1917). From the initial analysis of the peels, both the symmetry of the ovule and the precise organization of the vascular system remained unclear, as part of the ovule was removed by the saw cut that revealed the specimen.…”

New plant fossils from the Lower Cretaceous of the Parnaíba Basin, Northeastern Brazil: Southern Laurasia links

“…arrangement, associate to high-order cross veins preserving rare anastomoses in chevrons, approximate this morphotype to those found in previous described gnetophytes (Kunzmann et al 2009, 2011, Seward 2010, Ricardi-Branco et al 2013. Among the known fossils, such morphological features characterize Drewria potomacensis Crane (Crane & Upchurch Jr., 1987), described by Doyle and Hickey (1976) to the Zone I Potomac Group.…”

“…In extant conifers, besides the Cupressaceae, short and acute leaves that are oppositely arranged can also be found in the heterophilic shoots of Podocarpaceae (Page 1999, Seward 2010, Fontes & Dutra 2010, Mao et al 2012, Du et al 2013. In the absence of reproductive structures or preserved cuticles, we follow here the recommendation of Schweitzer (1974) …”

The Albian fern flora of Alexander Island, Antarctica

“…Adiantites was erected by Goeppert (1836) and it was used as a fossil taxon (form-genus) for fern-like fronds with cuneate pinnules resembling the extant fern Adiantum (Seward, 1910). However, the type species of Adiantites is a Carboniferous seed-fern and the use of this genus for ferns is not valid (Jennings, 1985).…”