CORDAIANTHUS DUQUESNENSIS SP. NOV., ANATOMICALLY PRESERVED OVULATE CONES FROM THE UPPER PENNSYLVANIAN OF OHIO

Four anatomically preserved cordaitean cones have been discovered in Upper Pennsylvanian sediments of Ohio, and these provide evidence for the description of Cor-daianthus duquesnensis sp. nov. Specimens consist of isolated shoots. Each exhibits sterile scales, ovule-bearing scales and scales from which ovules have apparently abscised. Cones are up to 5.5 mm long and 2.2 mm in maximum diameter, with fertile scales restricted to the distal region. Ovules occur singly at the tip of fertile scales and all are either immature or abortive. A comparison of scales and ovules at the apex with those in progressively more proximal regions forms the basis for interpreting several features of cone and ovule ontogeny. CORDAIANTHUS strobili are a relatively common component of many Pennsylvanian floras in North America and stratigraphically equivalent deposits of Europe. Both ovulate and pollen-producing fructifications occur in compression floras that yield cordaitean organs. Pollen cones are also well represented in floras of anatomically preserved remains (Daghlian and Taylor, 1979; Darrah, 1940; Delevoryas, 1953; Fry, 1956; Hirmer, 1933; Renault, 1879; Rothwell, 1977; Scott, 1919), but ovulate specimens are conspicuous by their scarcity in permineralized material. To date, only 18 sections of histologically preserved ovulate cordaitean strobili have been described (Bertrand, 1911). The sections are all from Stephanian sediments (Florin, 1951) near Saint Etin Cordaianthus williamsoni, C. grand'eury, C. zeilleri and C. lacattei (Renault, 1879). However, the small number of available sections, similar structural features and a common source of the material leads one to suspect that they may represent a single species. The same material has also been studied by Bertrand (1911), Schoute (1925), and Florin (1944, 1951). Possible ovulate Cordaianthus cones from Westphalian coal balls of England have been reported briefly by Wild and Lomax (1900), but to my knowledge, not subsequently described. The identity of the specimens, therefore, remains uncertain. An earlier report of ovulate Cordaianthus specimens from North American coal balls (Darrah, 1940) is apparently in error (Fry, 1956), and subsequent au' Received for publication 17 October 1980; revision accepted 18 January 1981. This study was supported by NSF grant no. DEB80-10793. thors have interpreted the specimens as pollenproducing cones. While the paucity of ovulate cordaitean strobili in permineralization material has not been adequately explained, two previously considered possibilities are either: 1) that the bracts and ovulate scales were abscised at maturity; or 2) that the strobili continued to grow as vegetative branches after the ovules had been shed (Schopf in Fry, 1956). An additional possibility is that the ovules were delicately attached to the scales and that they abscised at a relatively early stage. If the latter were true, then one would expect to eventually find specimens that show either immature ovules at the tips of some scales, or places from which more mature ovules have abscised, or both. The cones upon which the present report is based were discovered as the result of a search for specimens that show such features, and represent the first unquestionable ovulate cordaitean fructifications from North American permineralization material. Each cone bears ovules of several developmental stages. The specimens also exhibit a distinctive suite of features that separate them from previously described species of cordaitean strobili. As a result, they provide an opportunity to describe a new species of ovulate Cordaianthus, and to interpret some aspects of cone development and early ontogeny of the ovules. The name Cordaianthus duquesnensis sp. nov. is proposed for the specimens and signifies the stratum from which they were recovered. The cones are preserved by calcareous cellular permineralization, and occur in coal balls collected from a road cut on the south side of Ohio Route 22 approximately 8 km west of Steubenville, Ohio. The source of the material