Stigmaria

Stigmaria specimen collected from the cutoff locality near New Harmony, Indiana.

A Stigmaria (lycopsid rhizomorph) with a pyritized rind, which has a [delta][sup.34]S value of 31[per thousand], was recovered from poorly exposed mudrocks in the intertidal zone at ~949 m (Wagner et al.

Clement seemed to prefer collecting tree trunk and woody material of Lepidodendron, Sigillaria, Stigmaria, and Calamites, over leafy material as only three specimens of leaves (Pecopteris and Neuropteris) occur in the collection.

While the trunks of different varieties of scale trees can be characterized by the pattern of their scales, the roots are all very similar and have been given the generic name Stigmaria.

They're striated in the direction of the groove and are 320m-year-old fossil tree roots, from coal forests, called stigmaria.

pinnatifida, Sphenopteris matheti, Odontopteris obtusa, Mixoneura neuropteropteroides, Stigmaria (roots), Sphenophyllum oblongifolium, Alethopteris subelegans, Odontopteris cf.

Developmental dynamics of arborescent lycophytes - apical and lateral growth in Stigmaria ficoides.

Although several fine specimens of Phytolithus verrucosus (Stigmaria of current nomenclature) were located and Hopkins (1835a, p.

High organic matter in these swamp sediments may also have favored [CO.sub.2] uptake from the sediment, as suggested by the similarity in lacunal volume between Isogtes roots and fossil roots of the extinct Stigmaria (Karrfalt, 1980) and Pleuromeia (Munster) Corda (Grauvogel-Stamm, 1993), and this in mm would have favored the evolution of CAM (Osmond, 1984).

The first convincing argument for the terrestrial origin of coal had come from Logan's observations (1841) that Stigmaria were the roots of lycopsid trees in their original position of growth.

Lyell suggested that they look over a map of the region together and told Logan that the Geological Society was particularly interested in the observations they had both made on Stigmaria underclays (Lyell to Logan, 13 April 1843 & 27 April 1843, Logan Papers).