Abstract
Trilobites from the Appalachians of Virginia and Gaspé, Québec, that were attributed previously to the Swedish Ordovician genus Isbergia Warburg, 1925 are described and shown to belong to the Family Isocolidae. Isbergia virginica B. N. Cooper, 1953 is made the type species of a new genus Effnaspis. Cyphoniscus Salter, 1853, previously reported only from southern Ireland, northern England, and Kazakhstan, is described from eastern Gaspé.