Five new species, 1 new genus and 1 new family of late Cambrian and early Ordovician loricates are described. The new family Preacanthochitonidae contains the new genus Preacanthochiton with the new species P. cooperi, P. depressus and P. productus. In addition the new species Chelodes intermedius and C. depressus are described. Although the collection consists of separated plates, a formula is developed that gives a close approximation of the length of the complete animal. The morphological and systematic discussions are followed by general remarks on the origin and evolution of the loricates. A preliminary synoptical table of the class Loricata and a list of references completes the paper.