Opinions from W. D. Matthew 1907
- 'Arctoryctes belongs to Proscalopidae'
- 'Arctoryctes terrenus belongs to Arctoryctes'
- 'Blastomeryx advena belongs to Blastomeryx'
- 'Canis brachypus is recombined as Cynodesmus brachypus'
- 'Canis brachypus is recombined as Cynodesmus brachypus' according to Scott 1895
- 'Canis geismarianus is recombined as Nothocyon geismarianus'
- 'Canis geismarianus is recombined as Nothocyon geismarianus' according to Matthew 1899
- 'Canis geismarianus is recombined as Galecynus geismarianus' according to Cope 1879
- 'Canis lemur is recombined as Nothocyon lemur'
- 'Canis lemur is recombined as Nothocyon lemur' according to Wortman and Matthew 1899
- 'Canis lemur is recombined as Nothocyon lemur' according to Wortman and Matthew 1899
- 'Canis lemur is recombined as Nothocyon lemur' according to Matthew 1899
- 'Cynodesmus minor belongs to Cynodesmus'
- 'Cynodesmus thomsoni belongs to Cynodesmus'
- 'Desmathyus belongs to Tayassuidae'
- 'Desmathyus pinensis belongs to Desmathyus'
- 'Enhydrocyon basilatus belongs to Enhydrocyon'
- 'Enhydrocyon basilatus is recombined as Hyaenocyon basilatus' according to Cope 1879
- 'Enhydrocyon crassidens belongs to Enhydrocyon'
- 'Entoptychus curtus belongs to Entoptychus'
- 'Entoptychus formosus belongs to Entoptychus'
- 'Euhapsis gaulodon belongs to Euhapsis'
- 'Galecynus latidens is recombined as Nothocyon latidens'
- 'Hyaenocyon is a subjective synonym of Enhydrocyon'
- 'Hyaenocyon belongs to ' according to Cope 1879
- 'Hyaenocyon sectorius is recombined as Enhydrocyon sectorius'
- 'Hyaenocyon sectorius belongs to Hyaenocyon' according to Cope 1883
- 'Hypertragulus ordinatus belongs to Hypertragulus'
- 'Hypotemnodon is a subjective synonym of Mesocyon'
- 'Lepus macrocephalus belongs to Lepus'
- 'Lepus primigenius belongs to Lepus'
- 'Megalictis belongs to Mustelidae'
- 'Megalictis ferox belongs to Megalictis'
- 'Mesocyon robustus belongs to Mesocyon'
- 'Nimravus sectator belongs to Nimravus'
- 'Nothocyon gregorii belongs to Nothocyon'
- 'Nothocyon vulpinus belongs to Nothocyon'
- 'Oligobunis lepidus belongs to Oligobunis'
- 'Steneofiber brachyceps belongs to Steneofiber'
- 'Steneofiber sciuroides belongs to Steneofiber'
- 'Steneofiber simplicidens belongs to Steneofiber'
- 'Temnocyon coryphaeus is recombined as Mesocyon coryphaeus'
- 'Temnocyon josephi is recombined as Mesocyon josephi'
- 'Temnocyon josephi is recombined as Mesocyon josephi' according to Scott 1890
- 'Thinohyus belongs to Tayassuidae' according to Marsh 1875
- 'Thinohyus is a subjective synonym of Perchoerus'
- 'Thinohyus (Bothrolabis) siouxensis is recombined as Desmathyus siouxensis'
- 'Thinohyus lentus is recombined as Perchoerus lentus'