Opinions from W. K. Gregory 1910
- 'Achaenodontidae belongs to Nonruminantia'
- 'Albertogaudryidae belongs to Notoungulata'
- 'Allotheria was reranked as a suborder and belongs to Marsupialia'
- 'Amblypoda belongs to Ungulata'
- 'Ancylopoda belongs to Mesaxonia'
- 'Anicanodonta belongs to Xenarthra'
- 'Animalivora belongs to Chiroptera'
- 'Anomodontia was reranked as a suborder and belongs to Therapsida'
- 'Anoplotheriadae is corrected as Anoplotheriidae and belongs to Ruminantia'
- 'Anthracotheriidae belongs to Nonruminantia'
- 'Anthropoidea belongs to Primates'
- 'Antilocapridae belongs to Ruminantia'
- 'Archaeoceti is a subjective synonym of Zeuglodontia'
- 'Archaeohyracidae belongs to Toxodontia'
- 'Archonta belongs to Eutheria'
- 'Artiodactyla belongs to Paraxonia'
- 'Astrapotheria was reranked as a order and belongs to Notoungulata'
- 'Astrapotheriidae belongs to Astrapotheria'
- 'Barytheria belongs to Ungulata'
- 'Bovidae belongs to Ruminantia'
- 'Camelidae belongs to Ruminantia'
- 'Catarrhini was reranked as the unranked clade Catarrhina and belongs to Anthropoidea'
- 'Centetidae belongs to Zalambdodonta'
- 'Cercopithecidae belongs to Catarrhina'
- 'Cervidae belongs to Ruminantia'
- 'Cetacea belongs to Eutheria'
- 'Chiroptera belongs to Archonta'
- 'Chrysochloridae belongs to Zalambdodonta'
- 'Condylarthra was reranked as a suborder and belongs to Protungulata'
- 'Coryphodontidae belongs to Amblypoda'
- 'Creodonta was reranked as a unranked clade and belongs to Ferae'
- 'Cynodontia was reranked as a suborder and belongs to Therapsida'
- 'Dermoptera belongs to Archonta'
- 'Dichobunidae belongs to Nonruminantia'
- 'Dicotylidae belongs to Nonruminantia'
- 'Dimylidae belongs to Erinaceomorpha'
- 'Diprotodontia was reranked as a order and belongs to Marsupialia'
- 'Dromasauria belongs to Therapsida'
- 'Duplicidentata was reranked as a suborder and belongs to Glires'
- 'Edentata belongs to Eutheria'
- 'Embrithopoda belongs to Ungulata'
- 'Entelodontidae belongs to Nonruminantia'
- 'Erinaceidae belongs to Erinaceomorpha'
- 'Erinaceomorpha was reranked as a unranked clade and belongs to Lipotyphla'
- 'Eutheria belongs to Theria'
- 'Ferae belongs to Therictoidea'
- 'Fissipeda was reranked as the suborder Fissipedia and belongs to Ferae'
- 'Frugivora belongs to Chiroptera'
- 'Galeopithecidae belongs to Dermoptera'
- 'Giraffidae belongs to Ruminantia'
- 'Glires belongs to Rodentia'
- 'Henricosbornidae belongs to Notoungulata'
- 'Hippopotamidae belongs to Nonruminantia'
- 'Homalodotheria belongs to Notoungulata'
- 'Homalodotheriidae belongs to Homalodotheria'
- 'Hominidae belongs to Catarrhina'
- 'Hylobatidae belongs to Catarrhina'
- 'Hyopsodontidae belongs to Insectivora'
- 'Hypertragulidae belongs to Ruminantia'
- 'Hyraces belongs to Ungulata'
- 'Insectivora belongs to Therictoidea'
- 'Interatheridae is corrected as Interatheriidae and belongs to Toxodontia'
- 'Isotemnidae belongs to Astrapotheria'
- 'Lemures belongs to Prosimiae'
- 'Leptictidae belongs to Erinaceomorpha'
- 'Lipotyphla was reranked as a suborder and belongs to Insectivora'
- 'Litopterna was reranked as a suborder and belongs to Notoungulata'
- 'Loricata is a subjective synonym of Hicanodonta'
- 'Macraucheniidae belongs to Litopterna'
- 'Macroscelididae belongs to Menotyphla'
- 'Marsupialia was reranked as a order and belongs to Metatheria'
- 'Megachiroptera is a subjective synonym of Frugivora'
- 'Meniscotheriidae belongs to Condylarthra'
- 'Menotyphla belongs to Archonta'
- 'Merycodontidae belongs to Ruminantia'
- 'Mesaxonia belongs to Ungulata'
- 'Metatheria was reranked as a subclass and belongs to Theria'
- 'Microchiroptera is a subjective synonym of Animalivora'
- 'Mixodectidae belongs to Menotyphla'
- 'Monotremata belongs to Prototheria'
- 'Multituberculata is a subjective synonym of Allotheria'
- 'Mystacoceti was reranked as a order and belongs to Cetacea'
- 'Necrolestidae belongs to Zalambdodonta'
- 'Nesodontidae belongs to Toxodontia'
- 'Nonruminantia belongs to Artiodactyla'
- 'Notoungulata belongs to Ungulata'
- 'Odontoceti was reranked as a unranked clade and belongs to Cetacea'
- 'Oreodontidae belongs to Ruminantia'
- 'Pantolambdidae belongs to Taligrada'
- 'Pantolestidae belongs to Lipotyphla'
- 'Paraxonia belongs to Eutheria'
- 'Paucituberculata was reranked as a suborder and belongs to Marsupialia'
- 'Periptychidae belongs to Taligrada'
- 'Perissodactyla was reranked as a suborder and belongs to Mesaxonia'
- 'Phenacodontidae belongs to Condylarthra'
- 'Pholidota belongs to Edentata'
- 'Pilosa is a subjective synonym of Anicanodonta'
- 'Pinnipedia was reranked as a suborder and belongs to Ferae'
- 'Platyrrhini was reranked as the unranked clade Platyrrhina and belongs to Anthropoidea'
- 'Polyprotodonta was reranked as the suborder Polyprotodontia and belongs to Marsupialia'
- 'Potamogalidae belongs to Zalambdodonta'
- 'Primates belongs to Archonta'
- 'Proboscidea was reranked as a order and belongs to Ungulata'
- 'Promammalia belongs to Mammalia'
- 'Prosimiae belongs to Primates'
- 'Proterotheriidae belongs to Litopterna'
- 'Protodonta belongs to Promammalia'
- 'Prototheria belongs to Mammalia'
- 'Protungulata belongs to Ungulata'
- 'Protypotheriidae belongs to Toxodontia'
- 'Pyrotheria belongs to Notoungulata'
- 'Pyrotheriidae belongs to Pyrotheria'
- 'Rodentia belongs to Eutheria'
- 'Ruminantia belongs to Artiodactyla'
- 'Simiidae belongs to Catarrhina'
- 'Simplicidentata belongs to Glires'
- 'Solenodontidae belongs to Zalambdodonta'
- 'Soricidae belongs to Soricomorpha'
- 'Soricomorpha belongs to Insectivora'
- 'Taeniodonta belongs to Edentata'
- 'Taligrada belongs to Protungulata'
- 'Talpini was reranked as the family Talpidae and belongs to Soricomorpha'
- 'Tarsii belongs to Prosimiae'
- 'Therapsida was reranked as a order and belongs to Reptilia'
- 'Theria belongs to Mammalia'
- 'Therictoidea belongs to Eutheria'
- 'Therocephalia was reranked as a suborder and belongs to Therapsida'
- 'Toxodontia belongs to Notoungulata'
- 'Toxodontidae belongs to Toxodontia'
- 'Tragulidae belongs to Ruminantia'
- 'Triconodonta belongs to Metatheria'
- 'Trigonolestidae belongs to Nonruminantia'
- 'Trituberculata was reranked as a order and belongs to Metatheria'
- 'Tubulidentata belongs to Edentata'
- 'Tupaiidae belongs to Menotyphla'
- 'Typotheriidae belongs to Toxodontia'
- 'Uintatheriidae belongs to Amblypoda'
- 'Ungulata belongs to Eutheria'
- 'Xenarthra was reranked as a order and belongs to Edentata'
- 'Zalambdodonta was reranked as a unranked clade and belongs to Lipotyphla'
- 'Zeuglodontes is corrected as Zeuglodontia and belongs to Cetacea'