Ordovician Chitinozoa from Shropshire

Chitinozoan assemblages from the Llanvirnian, Llandeilian, and Caradocian sediments of the Shelve and Caradoc districts of Shropshire have been examined. Thirty-one species belonging to twelve genera are recorded and described; of these, nineteen species and one genus (Siphonochitina) are new. The genera Acanthochitina and Hercochitina are emended. The locations and lithologies of the samples are briefly described and the techniques used in preparing the chitinozoans for microscopic examination are outlined; it has been determined from an examination of material in thin section that these techniques do not appreciably affect the chitinozoans. The character of the chitinozoan fauna in Shropshire is traced from the base of the Llanvirnian to the top of the Caradocian, and the Ordovician faunas of Shropshire, the Baltic, and North Africa are compared. It is concluded that the British fauna, whilst having a distinct character of its own, compares fairly closely with that of the Baltic, but only remotely with that of North Africa. Other acid-resistant microfossils accompanying the chitinozoans are described briefly.