Studies on a new lower carboniferous flora from kingswood near pettycur, Scotland. I. Preliminary report

Abstract

A new Asbian flora preserved as calcareous permineralizations and as fusian has been discovered closely associated with the famous Pettycur flora in Fife, Scotland. This new flora occurs in limestones within a volcanogenic sequence at Kingswood, near Pettycur. The limestones are tentatively interpreted as having been deposited in a lake possibly within a crater. The plant fossil assemblage is dominated by fusainized pteridospermous remains which include stems, rachides, distal parts of fronds and pollen organs. Associated with these are numerous fragments of gymnospermous wood. Permineralized axes of the lycopod Oxroadia are also abundant and occur with megasporophylls of Achlamydocarpon-type. Sphenopsids and ferns are rare and always fusainized. The assemblage contains new taxa still to be named, such as two pollen organs showing intermediate features between Lyginopteridaceae and Medullosaceae and at least two species of Lyginorachis. Some gymnospermous stems with pycnoxylic wood and triangular pith also represent new taxa of unknown affinities. The occurrence of growth rings in some woody specimens is noted. Whilst this flora is of the same age as the Pettycur assemblage, the most significantly striking feature is that there is only one genus, Archaeocalamites, in common. This almost certainly must reflect an ecological control within the volcanic terrain.