Article: A new non-calcified alga from the upper Silurian of mid Wales

The alga, Powysia bassettii gen. et sp. nov., is described from the early Ludlow Series at Llangammarch Wells, Powys, mid Wales. The most complete specimen consists of a thallus differentiated into holdfast, stipe, and much branched distal region, all of which appear to have a tubular construction. Reproductive structures have not been found. Comparison is made with living and fossil algae, but the precise affinities of these Welsh fossils, in which a thallus of such marked morphological differentiation has an apparently simple internal structure, remain unresolved.