The British Rhætic Flora

Abstract

PROF. T. M. HARRIS, with experience of the Greenland Rhsetic flora behind him, has now studied the British Rhsetic beds and, with the application of new methods, described with considerable detail some of the few plants from these rocks (The British Rhsetic Flora, British Museum, 1938.) The main outcrop of Rhsetic rocks extends from Dorset to north Yorkshire, and it is from these alone that plant remains have been obtained, though smaller outcrops also occur in Wales, Northern Ireland and Scotland. The conception of the Rhaetic formation is that of a shallow sea, dotted with islands, and in this, slight changes in level isolated lagoons, which would soon become brackish or freshwater lakes. It is probably in such lakes that the plants grew. The plant-containing beds occur as strata between those containing fish and other marine remains, suggesting temporary incursions of the sea into the lagoon region. The Bristol locality seems to have supplied most of the specimens.