Species from the Highgate Formation of northwestern Vermont and the related Beekmantown Group of Quebec are treated. Sixteen named and 3 unnamed species are described; Diplozyga rossi (Valmy Formation, Nevada) and 'Plumulites' clarki are new. Thirteen generic names are used; Typhlokorynetes (based on Warburgella plana Raymond) and Marcouella (based on Lloydia pinguis Bradley) are new. The former is assigned to the new family Typhlokorynetidae, and the latter to the new subfamily Leiostegiinae. Metoptogyrus Raymond is considered synonymous with Niobella Reed. Strototropis and Leiostrototropis, both of Raymond, are considered synonymous with Protopliomerops Kobayashi.