Article: A revision of Acaste downingiae (Murchison) and related trilobites

Three species of Acaste, A. downingiae (Murchison), A. inflata (Salter), and A. subcaudata (Murchison); two species of Acastocephala gen. nov., A. macrops (Salter) and A. dudleyensis sp. nov.; and Acastoides constricta (Salter) are described from rocks of Wenlockian age from the West Midlands, Welsh Borderlands, and South Wales. Their relationships to later Silurian and early Devonian acastomorph genera are discussed.