Palaeostachya Andrewsii, a New Species of Calamitean Cone from the American Carboniferous

Abstract

WHILE PALAEOSTACHYA is one of the most interesting fossil cones assigned to the Calamitales and was considered by certain of the early workers to be the only true fructification of the group, the major portion of our anatomical knowledge of the genus is based on less than one-half dozen specimens from the Lancashire coal-measures. These were originally described by Williamson (1871Williamson ( , 1888 and the most recent and complete account (of the same specimens) is that of Hickling (1907). Thus almost 70 years have elapsed since the discovery of the fossil material on which most of our current knowledge is founded.The discovery of the present specimen was made in the summer of 1953 and by a curious coincidence (considering the long prior unproductive period) was contemporaneous with discoveries of several other specimens by other American workers'', In general the present specimen confirms the observations of Hickling on cone morphology and vascular anatomy of the sporangiophores although it differs from the English specimens in several characters of specific importance and illustrates a number of hitherto-undescribed anatomical details.The specimen has been named Palaeostochya andrewsii in honor of Professor

The Whole and the Parts: Relationships Between Floral Architecture and Floral Organ Shape, and Their Repercussions on the Interpretation of Fragmentary Floral Fossils1

“…Cuneate organs are also known from a number of various fossil plants. Subtending bracts (or sporangiophores) are cuneate in some lycophytes (Mazocarpon Benson;Schopf, 1941;Pigg, 1983), sphenophytes (Palaeostachya Weiss; Baxter, 1955), cycads (Androstrobus Schimper, Beania Carruthers, Harris, 1941Harris, , 1964Delemaya Klavins, Taylor, Krings & Taylor, Klavins et al, 2003), and many conifers (Ohsawa, 1994;Stockey, 1994). Ovules are cuneate in Pentoxylales (Sahni, 1948;Crane, 1985) and interseminal scales in Bennettitales (Harris, 1969;Crepet, 1974;Sharma, 1982;Pedersen et al, 1989;Nishida, 1994;Rothwell & Stockey, 2002;Stockey & Rothwell, 2003).…”

Early Permian silicified floras from the Perdasdefogu Basin (SE Sardinia): comparison and bio-chronostratigraphic correlation with the floras of the Autun Basin (Massif central, France)

“…In their general organization these cones are similar to those of Palaeostachya andrewsii (Baxter, 1954) from Pennsylvanian coal balls of Iowa based on an exceptionally preserved specimen allowing to recognize features not completely available in our material; in addition, the spores of the American cone are larger. A detailed study is necessary to decide of the taxonomic attribution of the present specimens which can also be compared to Palaeostachya (Volkmannia) gracilis cones described by Renault (1876; 1896) from the Lower Permian of Autun.…”

Palaeostachya Dircei N. Sp., an Authigenically Cemented Equisetalean Strobilus From the Middle Pennsylvanian of Southern Illinois

“…Palaeostachya dircei possesses 24 bracts which alternate from whorl to whorl, while P. schim- Matthew. 1906Baxter. 1955Abbott.…”

“…Permineralized specimens of equisetalean strobili are easily delimited to a generic and specific level because serial thin sections are easily prepared utilizing the cellulose acetate peel technique (Delevoryas, 1955;Baxter, 1955;Taylor, 1967;Good, 1975). The relationship between the sporangiophore and bract as well as other anatomical and morphological features of the fructifications are readily observable.…”