Archaeopteris is an extinct genus of progymnosperm tree with fern-like leaves. A useful index fossil, this tree is found in strata dating from the Upper Devonian to Lower Carboniferous, the oldest fos
Archaeopteris hibernica 2
A reconstruction of Archaeopteris macilenta from the Late Devonian, Walton Formation of Hancock, New York
A polished round of permineralised wood of Callixylon whiteanum from the Late Devonian Woodford Shale of Ada, Oklahoma
Calamites is a genus of extinct arborescent horsetails to which the modern horsetails are closely related. Unlike their herbaceous modern cousins, these plants were medium-sized trees, growing to heig
Archaeopteris
…transformation of Earth's climate during the Devonian before becoming extinct within a short period of time at the beginning of the Carboniferous period. Calamites Glossopteris…
The foliage (Annularia) of Calamites
A diagram of a pith cast of Calamites
Calamites sp., Estonian Museum of Natural History