Thisbemys corrugatus
Thisbemys elachistos
Thisbemys medius
Thisbemys perditus
Thisbemys sp.
Thisbemys uintensis
Thomomys bottae
Thomomys carsonensis
Thomomys gidleyi
Thomomys microdon
Thomomys orientalis
Thomomys potomacensis
Thomomys sp.
Thomomys talpoides
Thomomys townsendii
Thomomys umbrinus
Thryptacodon antiquus
Thryptacodon australis
Thryptacodon barae
Thryptacodon demari
Thryptacodon pseudarctos
Thryptacodon sp.
Thylacaelurus campester
Thylacaelurus montanus
Thylacaelurus sp.
Thylacodon pusillus
Thylacodon sp.
Ticholeptus sp.
Ticholeptus zygomaticus
Tillodon fodiens
Tillodon sp.
Tillomys parvidens
Tillomys senex
Tillomys sp.
Tinimomys graybulliensis
Tinimomys loomisi
Tinimomys sp.
Tinodon sp.
Tinuviel eurydice
Tinuviel sp.
Tisisthenes parvus
Tisisthenes sp.
Titanoides gidleyi
Titanoides looki
Titanoides major
Titanoides nanus
Titanoides primaevus
Titanoides sp.
Titanotylopus nebraskensis
Titanotylopus sp.
Tiznatzinia sp.
Tiznatzinia vanderhoofi
Tomarctus brevirostris
Tomarctus hippophaga
Tomarctus sp.
Toromeryx marginensis
Toromeryx sp.
Torrejonia sirokyi
Torrejonia sp.
Torrejonia wilsoni
Toxotherium hunteri
Toxotherium sp.
Tregomys pisinnus
Tregomys shotwelli
Tregomys sp.
Tregosorex holmani
Tregosorex sp.
Tremarctos floridanus
Tremarctos sp.
Trigenicus profectus
Trigenicus sp.
Trigonias osborni
Trigonias sp.
Trigonias wellsi
Trigonias yoderensis
Trigonictis cookii
Trigonictis macrodon
Trigonictis sp.
Triisodon crassicuspis
Triisodon quivirensis
Triisodon sp.
Trilaccogaulus lemhiensis
Trilaccogaulus montanensis
Trilaccogaulus ovatus
Trilaccogaulus sp.
Trinititherium slaughteri
Trinititherium sp.
Triplopides rieli
Triplopides sp.
Triplopus cubitalis
Triplopus implicatus
Triplopus obliquidens
Triplopus rhinocerinus
Triplopus sp.
Triplopus woodi
Tritemnodon agilis
Tritemnodon sp.
Tritemnodon strenuus
Trogolemur amplior
Trogolemur fragilis
Trogolemur myodes
Trogolemur sp.
Trogomys rupinimenthae
Trogomys sp.
Trogosus castoridens
Trogosus grangeri
Trogosus latidens
Trogosus sp.
Tubulodon atopum
Tubulodon pearcei
Tubulodon sp.
Tubulodon taylori
Tubulodon woodi
Turgidodon lillegraveni
Turgidodon madseni
Turgidodon petiminis
Turgidodon praesagus
Turgidodon rhaister
Turgidodon russelli
Turgidodon sp.
Tylocephalonyx skinneri
Tylocephalonyx sp.
Tyrannomys harkseni
Tyrannomys sp.
Tytthaena lichna
Tytthaena parrisi
Tytthaena sp.
Uintaceras radinskyi
Uintaceras sp.
Uintacyon acutus
Uintacyon asodes
Uintacyon bathygnathus
Uintacyon edax
Uintacyon jugulans
Uintacyon massetericus
Uintacyon rudis
Uintacyon sp.
Uintacyon vorax
Uintanius ameghini
Uintanius rutherfurdi
Uintanius sp.
Uintasorex montezumicus
Uintasorex parvulus
Uintasorex sp.
Uintatherium anceps
Uintatherium sp.
Umbogaulus galushai
Umbogaulus monodon
Umbogaulus sp.
Untermannerix copiosus
Untermannerix sp.
Unuchinia asaphes
Unuchinia diaphanes
Unuchinia dysmathes
Unuchinia sp.
Uriscus californicus
Uriscus sp.
Urocyon cinereoargenteus
Urocyon littoralis
Urocyon progressus
Urocyon sp.
Ursavus brevirhinus
Ursavus pawniensis
Ursavus primaevus
Ursavus sp.
Ursus abstrusus
Ursus americanus
Ursus arctos
Ursus maritimus
Ursus sp.
Utahia kayi
Utahia sp.
Utemylus latomius
Utemylus sp.
Varalphadon creber
Varalphadon crebreforme
Varalphadon sp.
Varalphadon wahweapensis
Vassacyon promicrodon
Vassacyon sp.
Viejadjidaumo magniscopuli
Viejadjidaumo sp.
Viridomys orbatus
Viridomys sp.
Viverravus acutus
Viverravus gracilis
Viverravus laytoni
Viverravus lutosus
Viverravus minutus
Viverravus politus
Viverravus rosei
Viverravus sicarius
Viverravus sp.
Viverravus vulpinus
Voorhies_cricetid parkeri
Vulpavus australis
Vulpavus canavus
Vulpavus completus
Vulpavus farsonensis
Vulpavus ovatus
Vulpavus palustris
Vulpavus profectus
Vulpavus sp.
Vulpes sp.
Vulpes stenognathus
Vulpes velox
Vulpes vulpes
Wallia scalopidens
Wallia sp.
Washakius insignis
Washakius izetti
Washakius laurae
Washakius sp.
Washakius woodringi
Weil_eucosmodontid woodi
Wilsoneumys planidens
Wilsoneumys sp.
Wilsonosorex bateslandensis
Wilsonosorex conulatus
Wilsonosorex sp.
Worlandia inusitata
Worlandia sp.
Wortmania otariidens
Wortmania sp.
Wyolestes apheles
Wyolestes dioctes
Wyolestes iglesius
Wyolestes sp.
Wyomomys bridgeri
Wyomomys sp.
Wyonycteris chalix
Wyonycteris sp.
Xanclomys mcgrewi
Xanclomys sp.
Xenacodon mutilatus
Xenacodon sp.
Xenicohippus craspedotum
Xenicohippus grangeri
Xenicohippus osborni
Xenicohippus sp.
Xenocranium pileorivale
Xenocranium sp.
Xyronomys sp.
Xyronomys swainae
Yaquius sp.
Yaquius travisi
Yatkolamys edwardsi
Yatkolamys sp.
Yoderimys bumpi
Yoderimys sp.
Yoderimys stewarti
Yoderimys yarmeri
Ysengrinia sp.
Zanycteris paleocena
Zanycteris sp.
Zapus burti
Zapus hudsonius
Zapus princeps
Zapus rinkeri
Zapus sandersi
Zapus sp.
Zapus sykesae
Zemiodontomys burkei
Zemiodontomys sp.
Zetamys nebraskensis
Zetamys sp.
Ziamys sp.
Ziamys tedfordi
Zodiolestes daimonelixensis
Zodiolestes sp.
Zygiocuspis goldingi
Zygiocuspis sp.
Zygolophodon proavus
Zygolophodon sp.