Opinions from J. Leidy 1873
- 'Acanthopteri belongs to Teleostei'
- 'Acipenser belongs to Placoganoidei'
- 'Acrodus belongs to Cestraciontidae'
- 'Acrodus humilis belongs to Acrodus'
- 'Agriochoerus belongs to Oreodontidae'
- 'Agriochoerus antiquus belongs to Agriochoerus'
- 'Agriochoerus latifrons belongs to Agriochoerus'
- 'Amia belongs to Cycloganoidei'
- 'Amia (Protamia) gracilis is recombined as Amia gracilis'
- 'Amia (Protamia) media is recombined as Amia media'
- 'Amia (Protamia) uintaensis is recombined as Amia uintaensis'
- 'Anchippodus belongs to Solidungula'
- 'Anchippodus riparius belongs to Anchippodus'
- 'Anchitheridae belongs to Solidungula'
- 'Anchitherium belongs to Anchitheridae'
- 'Anchitherium agreste belongs to Anchitherium'
- 'Anchitherium aurelianense belongs to Anchitherium'
- 'Anchitherium australe belongs to Anchitherium'
- 'Anchitherium condoni belongs to Anchitherium'
- 'Anosteira belongs to Chelonia'
- 'Anosteira ornata belongs to Anosteira'
- 'Anthracotheriidae [misspelled as Anthracotheridae] belongs to Omnivora'
- 'Antrodemus is a subjective synonym of Poicilopleuron'
- 'Archaeotherium is a subjective synonym of Elotherium'
- 'Archaeotherium mortoni is recombined as Elotherium mortoni'
- 'Artiodactyla belongs to Mammalia'
- 'Asteracanthus belongs to Ichthyodorulites'
- 'Asteracanthus siderius belongs to Asteracanthus'
- 'Atlantochelys belongs to Sphargididae'
- 'Atlantochelys mortoni belongs to Atlantochelys'
- 'Auchenia belongs to Camelidae'
- 'Auchenia californica belongs to Auchenia'
- 'Baena belongs to Chelonia'
- 'Baena affinis is a subjective synonym of Baena arenosa'
- 'Baena arenosa belongs to Baena'
- 'Baena undata is recombined as Chisternon undatum'
- 'Baptemys belongs to Chelonia'
- 'Bison belongs to Bovidae'
- 'Bos latifrons is recombined as Bison latifrons'
- 'Bovidae belongs to Ruminantia'
- 'Camelidae belongs to Ruminantia'
- 'Canidae belongs to Carnivora'
- 'Canis belongs to Canidae'
- 'Canis (Epicyon) haydeni is recombined as Canis haydeni'
- 'Canis indianensis belongs to Canis'
- 'Canis occidentalis belongs to Canis'
- 'Canis primaevus belongs to Canis' according to Leidy 1854
- 'Canis primaevus is replaced by Canis indianensis'
- 'Canis saevus belongs to Canis'
- 'Canis vafer belongs to Canis'
- 'Carnivora belongs to Mammalia'
- 'Cervidae belongs to Ruminantia'
- 'Cestraciontidae belongs to Plagiostomi'
- 'Cetacea belongs to Mammalia'
- 'Chamaeleo [misspelled as Chameleo] belongs to Lacertilia'
- 'Chamaeleo pristinus [misspelled as Chameleo pristinus] belongs to Chameleo'
- 'Chelonii is corrected as Chelonia and belongs to Reptilia'
- 'Chisternon belongs to Chelonia'
- 'Cladocyclus belongs to Sphyraenidae'
- 'Cladocyclus occidentalis belongs to Cladocyclus'
- 'Cladodus belongs to Hybodontidae'
- 'Cladodus mortifer belongs to Cladodus'
- 'Cladodus occidentalis belongs to Cladodus'
- 'Clidastes belongs to Mosasauria'
- 'Clidastes affinis belongs to Clidastes'
- 'Clidastes iguanavus belongs to Clidastes'
- 'Clidastes intermedius belongs to Clidastes'
- 'Clidastes propython belongs to Clidastes'
- 'Clupea belongs to Clupeidae'
- 'Clupea alta belongs to Clupea'
- 'Clupea humilis belongs to Clupea'
- 'Clupeidae belongs to Teleostei'
- 'Corax is a subjective synonym of Galeocerdo'
- 'Corax falcatus is recombined as Galeocerdo falcatus'
- 'Crocodilia belongs to Reptilia'
- 'Crocodilus aptus belongs to Crocodilus'
- 'Crocodilus elliottii belongs to Crocodilus'
- 'Crocodylus is corrected as Crocodilus and belongs to Crocodilia'
- 'Cycloganoidei belongs to Ganoidei'
- 'Cynocercus belongs to Sphargididae'
- 'Cynocercus incisus belongs to Cynocercus'
- 'Cyprinidae belongs to Teleostei'
- 'Delphinidae belongs to Cetacea'
- 'Dicotyles belongs to Suidae'
- 'Dicotyles pristinus belongs to Dicotyles'
- 'Dicotyles torquatus belongs to Dicotyles'
- 'Dinoceras is a subjective synonym of Uintatherium'
- 'Dinoceras mirabilis is a subjective synonym of Uintatherium robustum'
- 'Dinosauria belongs to Reptilia'
- 'Edaphodon belongs to Edaphodontidae'
- 'Edaphodon mirificus belongs to Edaphodon'
- 'Edaphodontidae belongs to Holocephali'
- 'Elephas belongs to Proboscidea'
- 'Elephas americanus belongs to Elephas'
- 'Elephas americanus is recombined as Mastodon americanus'
- 'Elephas columbi is a subjective synonym of Elephas americanus'
- 'Elephas imperator is a subjective synonym of Elephas americanus'
- 'Elephas jacksoni is a subjective synonym of Elephas americanus'
- 'Elephas texianus is a subjective synonym of Elephas americanus'
- 'Elephas texianus belongs to Elephas' according to Owen 1858
- 'Elotherium belongs to Anthracotheridae'
- 'Elotherium imperator belongs to Elotherium'
- 'Elotherium lentus belongs to Elotherium'
- 'Elotherium superbus is corrected as Elotherium superbum and belongs to Elotherium'
- 'Emydidae belongs to Chelonia'
- 'Emys belongs to Emydidae'
- 'Emys carteri is a subjective synonym of Testudo corsoni'
- 'Emys culbertsonii is a subjective synonym of Testudo nebrascensis'
- 'Emys haydeni is a subjective synonym of Emys wyomingensis'
- 'Emys hemispherica is a subjective synonym of Testudo nebrascensis'
- 'Emys jeanesi is a subjective synonym of Emys wyomingensis'
- 'Emys oweni is a subjective synonym of Testudo nebrascensis'
- 'Emys petrolei belongs to Emys'
- 'Emys stevensonianus is a subjective synonym of Emys wyomingensis'
- 'Emys wyomingensis belongs to Emys'
- 'Enchodus belongs to Sphyraenidae'
- 'Enchodus dirus is recombined as Phasganodus dirus'
- 'Enchodus shumardi belongs to Enchodus'
- 'Entelodon is a subjective synonym of Elotherium'
- 'Eobasileus is a subjective synonym of Uintatherium'
- 'Equidae belongs to Solidungula'
- 'Equus belongs to Equidae'
- 'Equus (Protohippus) was reranked as Protohippus and belongs to Equidae'
- 'Equus (Protohippus) perditus is recombined as Protohippus perditus'
- 'Equus complicatus is a subjective synonym of Equus major'
- 'Equus excelsus is a subjective synonym of Equus occidentalis'
- 'Equus major belongs to Equus'
- 'Equus occidentalis belongs to Equus'
- 'Equus pacificus is a subjective synonym of Equus occidentalis'
- 'Equus parvulus is recombined as Anchitherium parvulus'
- 'Eumylodus belongs to Edaphodontidae'
- 'Eumylodus laqueatus belongs to Eumylodus'
- 'Felidae belongs to Carnivora'
- 'Felis belongs to Felidae'
- 'Felis atrox belongs to Felis'
- 'Felis augustus belongs to Felis'
- 'Galeocerdo belongs to Squalidae'
- 'Mosasaurus mitchelli is a subjective synonym of Atlantochelys mortoni'
- 'Glyptosaurus belongs to Lacertilia'
- 'Glyptosaurus ocellatus belongs to Glyptosaurus'
- 'Graphiodon belongs to Delphinidae'
- 'Hadrodus belongs to Rhomboganoidei'
- 'Hadrodus priscus belongs to Hadrodus'
- 'Hadrohyus belongs to Omnivora'
- 'Hadrohyus supremus belongs to Hadrohyus'
- 'Hadrosaurus foulkii belongs to Hadrosaurus'
- 'Hipparion belongs to Equidae'
- 'Hippodon speciosus is recombined as Hipparion speciosum'
- 'Hipposyus belongs to Omnivora'
- 'Hipposyus formosus belongs to Hipposyus'
- 'Holcodus coryphaeus is recombined as Lestosaurus coryphaeus'
- 'Holocephali belongs to Elasmobranchii'
- 'Hybemys belongs to Emydidae'
- 'Hybemys arenarius belongs to Hybemys'
- 'Hybodontes is corrected as Hybodontidae and belongs to Plagiostomi'
- 'Hyopsodus belongs to Omnivora'
- 'Hyopsodus minusculus belongs to Hyopsodus'
- 'Hyopsodus paulus belongs to Hyopsodus'
- 'Hypamia belongs to Cycloganoidei'
- 'Hypamia elegans belongs to Hypamia'
- 'Hyrachyus belongs to Anchitheridae'
- 'Hyrachyus agrarius belongs to Hyrachyus'
- 'Hyrachyus agrestis is a subjective synonym of Hyrachyus agrarius'
- 'Hyrachyus eximius belongs to Hyrachyus'
- 'Ichthyodorulithes is corrected as Ichthyodorulites and belongs to Elasmobranchii'
- 'Insectivora belongs to Mammalia'
- 'Labroidei is corrected as Labridae and belongs to Teleostei'
- 'Lacertilia belongs to Reptilia'
- 'Lamna belongs to Squalidae'
- 'Lamna acuminata belongs to Lamna'
- 'Lamna cuspidata belongs to Lamna'
- 'Lamna elegans belongs to Lamna'
- 'Lamna mantellii is recombined as Oxyrhina mantellii'
- 'Lamna texana belongs to Lamna'
- 'Lepidosteus atrox belongs to Lepidosteus'
- 'Lepidosteus notabilis belongs to Lepidosteus'
- 'Lepidosteus simplex belongs to Lepidosteus'
- 'Lepisosteus [misspelled as Lepidosteus] belongs to Rhomboganoidei'
- 'Leptomeryx belongs to Cervidae'
- 'Leptomeryx evansi belongs to Leptomeryx'
- 'Lestosaurus belongs to Mosasauria'
- 'Limnohyus belongs to Anchitheridae'
- 'Limnohyus is a subjective synonym of Palaeosyops'
- 'Limnohyus laevidens is a subjective synonym of Palaeosyops paludosus'
- 'Limnohyus laticeps belongs to Limnohyus'
- 'Limnohyus robustus is a subjective synonym of Palaeosyops major'
- 'Limnotherium elegans is recombined as Microsyops elegans'
- 'Limnotherium tyrannus belongs to Limnotherium'
- 'Liodon dyspelor is recombined as Tylosaurus dyspelor'
- 'Lophiodon belongs to Anchitheridae'
- 'Lophiodon bairdianus is a subjective synonym of Hyrachyus agrarius'
- 'Lophiodon isselense belongs to Lophiodon'
- 'Lophiodon modestus is recombined as Hyrachyus modestus'
- 'Lophiodon nanus is recombined as Hyrachyus nanus'
- 'Lophiotherium belongs to Anchitheridae'
- 'Lophiotherium sylvaticum belongs to Lophiotherium'
- 'Loxolophodon is a subjective synonym of Uintatherium'
- 'Lutra belongs to Mustelidae'
- 'Lutra piscinaria belongs to Lutra'
- 'Macrosaurus proriger is recombined as Tylosaurus proriger'
- 'Malacopteri belongs to Teleostei'
- 'Manatus belongs to Sirenia'
- 'Mastodon belongs to Proboscidea'
- 'Mastodon andium belongs to Mastodon'
- 'Mastodon angustidens belongs to Mastodon'
- 'Mastodon longirostris belongs to Mastodon'
- 'Mastodon mirificum [misspelled as Mastodon mirificus] belongs to Mastodon'
- 'Mastodon obscurum [misspelled as Mastodon obscurus] belongs to Mastodon'
- 'Mastodon shepardi is a subjective synonym of Mastodon obscurus'
- 'Megaceratops is a subjective synonym of Megacerops'
- 'Megacerops belongs to Proboscidea'
- 'Megacerops coloradensis belongs to Megacerops'
- 'Megalomeryx niobrarensis belongs to Megalomeryx'
- 'Megatherium jeffersonii [misspelled as Megalonyx jeffersoni] belongs to Megalonyx'
- 'Merychippus belongs to Equidae'
- 'Merychippus mirabilis belongs to Merychippus'
- 'Merychyus elegans belongs to Merychyus'
- 'Merychyus major belongs to Merychyus'
- 'Merychyus medius belongs to Merychyus'
- 'Merycochoerus belongs to Oreodontidae'
- 'Merycochoerus proprius belongs to Merycochoerus'
- 'Merycochoerus rusticus belongs to Merycochoerus'
- 'Merycodus belongs to Cervidae'
- 'Merycodus necatus belongs to Merycodus'
- 'Merycoidodon is a subjective synonym of Oreodon'
- 'Merycoidodon culbertsonii is recombined as Oreodon culbertsoni'
- 'Microsus belongs to Omnivora'
- 'Microsus cuspidatus belongs to Microsus'
- 'Microsyops belongs to Omnivora'
- 'Microsyops gracilis is a subjective synonym of Microsyops elegans'
- 'Mosasauria belongs to Reptilia'
- 'Mosasaurus belongs to Mosasauria'
- 'Muridae belongs to Rodentia'
- 'Mustelidae belongs to Carnivora'
- 'Myliobatis is corrected as Myliobates and belongs to Raiae'
- 'Mylocyprinus belongs to Cyprinidae'
- 'Mylocyprinus robustus belongs to Mylocyprinus'
- 'Mysops belongs to Muridae'
- 'Mysops fraternus belongs to Mysops'
- 'Mysops minimus belongs to Mysops'
- 'Notharctus belongs to Solidungula'
- 'Notharctus robustior is recombined as Hipposyus robustior'
- 'Notharctus tenebrosus belongs to Notharctus'
- 'Nothosaurops occiduus is recombined as Nothosaurus occiduus'
- 'Nothosaurus belongs to Sauropterygia'
- 'Oligosimus belongs to Sauropterygia'
- 'Oligosimus grandaevus belongs to Oligosimus'
- 'Omnivora belongs to Artiodactyla'
- 'Omomys belongs to Insectivora'
- 'Omomys carteri belongs to Omomys'
- 'Oncobatis belongs to Raiae'
- 'Oncobatis pentagonus belongs to Oncobatis'
- 'Oreodon belongs to Oreodontidae'
- 'Oreodon affinis belongs to Oreodon'
- 'Oreodon bullatus belongs to Oreodon'
- 'Oreodon hybridus belongs to Oreodon'
- 'Oreodon major belongs to Oreodon'
- 'Oreodon superbus belongs to Oreodon'
- 'Oreodontidae belongs to Ruminantia'
- 'Otodus belongs to Squalidae'
- 'Otodus divaricatus belongs to Otodus'
- 'Otodus semiplicatus belongs to Otodus'
- 'Oxyrhina belongs to Squalidae'
- 'Oxyrhina extenta belongs to Oxyrhina'
- 'Palaeacodon belongs to Insectivora'
- 'Palaeacodon verus belongs to Palaeacodon'
- 'Palaeosyops belongs to Anchitheridae'
- 'Palaeosyops humilis is recombined as Limnohyus humilis'
- 'Palaeosyops junior is a subjective synonym of Palaeosyops junius'
- 'Palaeosyops junius belongs to Palaeosyops'
- 'Palaeosyops major belongs to Palaeosyops'
- 'Palaeosyops paludosus belongs to Palaeosyops'
- 'Palaeotherium bairdii [misspelled as Anchitherium bairdi] belongs to Anchitherium'
- 'Palauchenia magna belongs to Palauchenia'
- 'Paramys belongs to Sciuridae'
- 'Paramys delicatior belongs to Paramys'
- 'Paramys delicatissimus belongs to Paramys'
- 'Paramys delicatus belongs to Paramys'
- 'Patriofelis belongs to Carnivora'
- 'Patriofelis ulta belongs to Patriofelis'
- 'Perissodactyla was reranked as a order and belongs to Mammalia'
- 'Petalodus belongs to Cestraciontidae'
- 'Petalodus allegheniensis [misspelled as Petalodus alleghaniensis] belongs to Petalodus'
- 'Petalodus destructor is a subjective synonym of Petalodus alleghaniensis'
- 'Phareodus belongs to Cycloganoidei'
- 'Phareodus acutus belongs to Phareodus'
- 'Phasganodus belongs to Sphyraenidae'
- 'Pimelodus belongs to Siluridae'
- 'Pimelodus antiquus belongs to Pimelodus'
- 'Placoganoidei belongs to Ganoidei'
- 'Plagiostomi was reranked as a order and belongs to Elasmobranchii'
- 'Poekilopleuron [misspelled as Poicilopleuron] belongs to Dinosauria'
- 'Poekilopleuron bucklandii [misspelled as Poicilopleuron bucklandi] belongs to Poicilopleuron'
- 'Poicilopleuron valens belongs to Poicilopleuron'
- 'Polycotylus latipinnis belongs to Polycotylus'
- 'Polygonodon audax is recombined as Xiphactinus audax'
- 'Pontobasileus belongs to Zeuglodontia'
- 'Pontobasileus tuberculatus belongs to Pontobasileus'
- 'Proboscidea was reranked as a order and belongs to Mammalia'
- 'Procamelus belongs to Camelidae'
- 'Procamelus gracilis belongs to Procamelus'
- 'Procamelus occidentalis belongs to Procamelus'
- 'Procamelus robustus belongs to Procamelus'
- 'Protautoga belongs to Labridae'
- 'Protocamelus virginiensis is recombined as Procamelus virginiensis'
- 'Protohippus placidus is recombined as Merychippus placidus'
- 'Protostega gigas belongs to Protostega'
- 'Protostega neptunia is a subjective synonym of Atlantochelys mortoni'
- 'Protostega tuberosa belongs to Protostega'
- 'Ptychodus belongs to Cestraciontidae'
- 'Ptychodus altior belongs to Ptychodus'
- 'Ptychodus mortoni belongs to Ptychodus'
- 'Ptychodus occidentalis belongs to Ptychodus'
- 'Ptychodus whipplei [misspelled as Ptychodus whippleyi] belongs to Ptychodus'
- 'Pycnodus belongs to Rhomboganoidei'
- 'Pycnodus carolinensis belongs to Pycnodus'
- 'Pycnodus faba belongs to Pycnodus'
- 'Pycnodus robustus belongs to Pycnodus'
- 'Raiae belongs to Plagiostomi'
- 'Rhamphosaurus is replaced by Tylosaurus'
- 'Rhinoceros belongs to Rhinocerotidae'
- 'Rhinoceros crassus belongs to Rhinoceros'
- 'Rhinoceros hesperius belongs to Rhinoceros'
- 'Rhinoceros occidentalis is a subjective synonym of Rhinoceros pacificus'
- 'Rhinoceros pacificus belongs to Rhinoceros'
- 'Rhinocerotidae belongs to Solidungula'
- 'Rhinosaurus is replaced by Tylosaurus'
- 'Rhomboganoidei belongs to Ganoidei'
- 'Rodentia belongs to Mammalia'
- 'Ruminantia belongs to Artiodactyla'
- 'Saniva major belongs to Saniva'
- 'Saniwa [misspelled as Saniva] belongs to Lacertilia'
- 'Saniwa ensidens [misspelled as Saniva ensidens] belongs to Saniva'
- 'Sauropterygia was reranked as a order and belongs to Reptilia'
- 'Sciuravus belongs to Sciuridae'
- 'Sciuravus nitidus belongs to Sciuravus'
- 'Sciuravus undans belongs to Sciuravus'
- 'Sciuridae belongs to Rodentia'
- 'Sicarius extinctus is a subjective synonym of Petalodus alleghaniensis'
- 'Siluridae belongs to Malacopteri'
- 'Sinopa belongs to Carnivora'
- 'Sinopa eximia belongs to Sinopa'
- 'Sinopa rapax belongs to Sinopa'
- 'Sirenia was reranked as a order and belongs to Mammalia'
- 'Solidungula was reranked as a suborder and belongs to Perissodactyla'
- 'Sphargididae belongs to Chelonia'
- 'Sphyraenidae belongs to Acanthopteri'
- 'Squalidae belongs to Plagiostomi'
- 'Stylemys nebrascensis is recombined as Testudo nebrascensis'
- 'Stylemys oregonensis is recombined as Testudo oregonensis'
- 'Suidae belongs to Omnivora'
- 'Testudinidae belongs to Chelonia'
- 'Testudo belongs to Testudinidae'
- 'Testudo (Stylemys) niobrarensis is recombined as Testudo niobrarensis'
- 'Testudo corsoni belongs to Testudo'
- 'Tinoceras is a subjective synonym of Uintatherium'
- 'Trionychidae belongs to Chelonia'
- 'Trionyx belongs to Trionychidae'
- 'Trionyx guttatus belongs to Trionyx'
- 'Trionyx uintaensis belongs to Trionyx'
- 'Trogosus is a subjective synonym of Anchippodus'
- 'Trogosus castoridens is a subjective synonym of Anchippodus riparius'
- 'Trogosus vetulus is recombined as Anchippodus vetulus'
- 'Trygon belongs to Raiae'
- 'Tylosaurus belongs to Mosasauria'
- 'Tylosteus belongs to Lacertilia'
- 'Tylosteus ornatus belongs to Tylosteus'
- 'Uintacyon belongs to Carnivora'
- 'Uintamastix is a subjective synonym of Uintatherium'
- 'Uintamastix atrox is a subjective synonym of Uintatherium robustum'
- 'Uintatherium belongs to Proboscidea'
- 'Uintatherium robustum belongs to Uintatherium'
- 'Washakius belongs to Insectivora'
- 'Washakius insignis belongs to Washakius'
- 'Xiphactinus belongs to Siluridae'
- 'Xystracanthus belongs to Ichthyodorulites'
- 'Xystracanthus arcuatus belongs to Xystracanthus'
- 'Zeuglodontes is corrected as Zeuglodontia and belongs to Mammalia'