Lower Caradocian (upper Ordovician) Chitinozoa from North Wales

Glanrafon (Ordovician) chitinozoan assemblages are described from the River Glaslyn area of North Wales. The rocks from which these Chitinozoa were collected have been metamorphosed to slate grade. The Chitinozoa are used to date the succession as Lower Caradocian and to correlate within the area. The fauna is compared with material described from other areas, principally from Shropshire. One new species, Cyathochitina concava, is described.