- ****igned to Palaeostachya, and the stem ****igned to
either Calamites or
Arthroxylon depending on
whether it is
preserved as a cast or a petrifaction. All...
- †Arctinurus †Arctomeristina †Arisaigia †Arrectocrinus †Arrectocrinus
iowensis †
Arthroxylon †Asphaltinella †Asterophyllites †Asterophyllites
multifolia †Asthenophyllum...
- †Arthraria †Arthraria
rogersensis †Arthropitys †Arthropitys
communis †
Arthroxylon †Asol**** †Aspidopora †Aspidopora
newberryi †Astarella †Astartella –...
