Opinions from J. Clark and J. R. Beerbower 1967
- 'Allops is a subjective synonym of Menodus'
- 'Allops crassicornis is recombined as Menodus crassicornis'
- 'Allops serotinus is recombined as Menodus serotinus'
- 'Allops walcotti is recombined as Menodus walcotti'
- 'Anchitherium celer is recombined as Mesohippus celer'
- 'Brontops is a subjective synonym of Menodus'
- 'Brontops robustus is recombined as Menodus robustus'
- 'Brontops validus is a subjective synonym of Menodus dispar'
- 'Brontotherium is a subjective synonym of Menodus'
- 'Campylocynodon is a subjective synonym of Parictis'
- 'Campylocynodon personi is recombined as Parictis personi'
- 'Daphoenus dodgei is recombined as Daphoenocyon dodgei'
- 'Diploclonus is a subjective synonym of Menodus'
- 'Diploclonus amplus is recombined as Menodus amplus'
- 'Hoplophoneus oharrai belongs to Hoplophoneus'
- 'Megacerops is a subjective synonym of Menodus'
- 'Menops is a subjective synonym of Menodus'
- 'Merycoidodon lewisi belongs to Merycoidodon'
- 'Mesohippus grandis belongs to Mesohippus'
- 'Mesohippus montanensis is a subjective synonym of Mesohippus hypostylus'
- 'Mesohippus portentus is a subjective synonym of Mesohippus hypostylus'
- 'Mesohippus proteulophus is a subjective synonym of Mesohippus hypostylus'
- 'Mesohippus viejensis belongs to Mesohippus'
- 'Mustelavus belongs to Mustelidae'
- 'Mustelavus priscus belongs to Mustelavus'
- 'Mustelavus priscus belongs to Mustelavus' according to Hough 1948
- 'Parictis parvus belongs to Parictis'
- 'Poebrotherium andersoni belongs to Poebrotherium'
- 'Symborodon is a subjective synonym of Menodus'
- 'Symborodon hypoceras is recombined as Menodus hypoceras'
- 'Symborodon torvus is recombined as Menodus torvus'
- 'Titanotherium is a subjective synonym of Menodus'