Hundred Species of the Genus Peronopsis Hawle et Corda, 1847. Monograph

The data on the genus Peronopsis, including 116 species and subspecies, that is, at least half of Middle Cambrian agnostians, are completely revised. The revision is based on the order of the formation of pygidial characters in ontogeny. A convenient taxonomic system of abundant species of this genus is proposed. It is shown that the sequence of the formation of…