Structure of Some Carboniferous Seeds from American Coal Fields

Abstract

1. Structurally preserved seeds were found in coal ball material collected under the auspices of the Illinois State Geological Survey by Dr. A. C. Noe of the University of Chicago. The source of the coal balls was from southern Illinois and Indiana in coal no. 5, which is in the Allegheny group of the Upper Pennsylvanian. 2. The seeds described are Conostoma oblongum Will. of the order Lagenostomales, and Pachytesta gigantea Br. of the order Trigonocarpales. This is the first description of Pachytesta from American coal balls. 3. Illustrations of Lagenostoma ovoides from the British Coal Measures, and of Pachytesta gigantea, Conostoma oblongum, Cardiocarpon, and Trigonocarpon hookeri from the American Coal Measures, are used to demonstrate similarity in development of Paleozoic seeds with those of modern gymnosperms, and to show variation in ontogeny at the time of petrifaction.