New ammonoid records from eastern North America are described as part of a sequence of thirty successive faunas recognized especially in the Middle and Upper Devonian. Most of these assemblages occur in the New York succession, but those occurring elsewhere are integrated with that succession as far as evidence allows. Critical ammonoid sequences in North Africa and Europe are described for the pre-Famennian Devonian. This enables comments to be made on the correlation of the America faunas. Anarcestes is described from New York. From the pre-Tioga Bentonite Onondaga Limestone equivalents in Virginia and West Virginia, two goniatite faunas are distinguished, an earlier with abundant agoniatitids, including Agoniatites oliveri sp. nov., and a later fauna with Foordites buttsi. From near Salem, Virginia, a rich barytized fauna is described with Cabrieroceras plebeiforme, Agoniatites, and Holzapfeloceras croyi sp. nov. which is thought to correlate with the Werneroceras Bed of New York, and with the Cabrieroceras-bearing levels of Morocco, Algeria, the Montagne Noire, Czechoslovakia, and the Rhenish Schiefergebirge which, in those areas, is usually taken to mark the basal Givetian. Higher Givetian faunas in the Appalachians include levels with Maenioceras, Sobolewia, and tornoceratids. From West Virginia are described Koenenites lamellosus kirchgasseri subsp. nov., Lobotornoceras hassoni sp. nov., Epitornoceras, and ?Pharciceras from horizons thought to be equivalent to pre-Genundewa strata in New York. This fauna is thought to correlate with European early Frasnian horizons. Faunas at approximately the Genundewa level including Probeloceras and Manticoceras are recognized in West Virginia. A fauna with Platyclymenia, Cyrtoclymenia, and Sporadoceras is reported from Lorain County, Ohio, and a higher level with Cymaclymenia is described from the same area. These comprise the first records of clymenids from eastern North America. A Middle Devonian silicified fauna with Cabrieroceras is described from Nevada and compared with the eastern Middle Devonian faunas. A specimen of Tornoceras is described which is the first Devonian goniatite recorded from Bolivia.