# List of the Cenozoic life of Wyoming

This list of the Cenozoic life of Wyoming contains the various prehistoric life-forms whose fossilized remains have been reported from within the US state of Wyoming and are between 66 million and 10,000 years of age.

## A

* A
* B
* C
* D
* E
* F
* G
* H
* I
* J
* K
* L
* M
* N
* O
* P
* Q
* R
* S
* T
* U
* V
* W
* X
* Y
* Z
* †Aaptoryctes
** †Aaptoryctes ivyi
* †Absarokius
** †Absarokius abbotti
** †Absarokius gazini – type locality for species
** †Absarokius metoecus – type locality for species
* †Abuta – or unidentified related form
* †Acacia
** †Acacia lamarensis
** †Acacia macrosperma
** †Acacia wardii
* †Acarictis
** †Acarictis ryani – type locality for species
* Accipiter
** A living Accipiter gentilis, or northern goshawk Accipiter gentilis
** †Accipiter striatus
* Acer
** †Acer lesquereuxi
** †Acer newberryi
** †Acer silberlingii
** †Acer vivarium
* †Aceroryctes – type locality for genus
** †Aceroryctes dulcis – type locality for species
* †Achaenodon
** †Achaenodon insolens – type locality for species
** †Achaenodon robustus – type locality for species
* †Acidomomys – type locality for genus
** †Acidomomys hebeticus – type locality for species
* †Acmeodon
** †Acmeodon secans
* †Acocephalus
** †Acocephalus adae – type locality for species
* †Acritoparamys
** †Acritoparamys atavus
** †Acritoparamys atwateri
** †Acritoparamys francesi
** †Acritoparamys wyomingensis
* Living Acrostichum, or leather fernsAcrostichum
** †Acrostichum hesperium
* †Adilophontes – type locality for genus
** †Adilophontes brachykolos – type locality for species
* †Adjidaumo
** †Adjidaumo burkei – tentative report
** †Adjidaumo craigi – or unidentified comparable form
** †Adjidaumo minimus
* Fossilized shell of the Early Cretaceous-Oligocene turtle Adocus†Adocus
* †Adunator
** †Adunator fredericki
** †Adunator ladae
** †Adunator martinezi
* Aegialia
** †Aegialia rupta – type locality for species
* Aegolius
** †Aegolius acadicus
** Aegolius funereus
* Life restoration of the Miocene camel Aepycamelus, or the long-necked camel. Heinrich Harder (1920). †Aepycamelus
* †Aerugoamnis – type locality for genus
** †Aerugoamnis paulus – type locality for species
* †Aesculus
** †Aesculus antiquorum
** †Aesculus hickeyi
* †Afairiguana – type locality for genus
** †Afairiguana avius – type locality for species
* †Ageina
** †Ageina tobieni
* †Ageitodendron
** †Ageitodendron matthewi
* Agelaius
** †Agelaius phoeniceus
* †Agnotocastor
** †Agnotocastor galushai – type locality for species
* Life restoration of the Eocene-Oligocene even-toed ungulate Agriochoerus †Agriochoerus
** †Agriochoerus maximus
** †Agriochoerus minimus – or unidentified comparable form
* Ailanthus
** †Ailanthus lesquereuxi
* †Alagomys
** †Alagomys russelli – type locality for species
* †Alastor
** †Alastor solidescens – type locality for species
* †Albertanella – or unidentified comparable form
** †Albertanella minuta
* Alces
** †Alces alces
* †Aletodon
** †Aletodon conardae – type locality for species
** †Aletodon gunnelli – type locality for species
** †Aletodon quadravus
* Restoration of the Miocene deer relative Aletomeryx †Aletomeryx
** †Aletomeryx gracilis
* †Aletornis – type locality for genus
** †Aletornis bellus – type locality for species
** †Aletornis gracilis – type locality for species
** †Aletornis nobilis – type locality for species
** †Aletornis pernix – type locality for species
** †Aletornis venustus – type locality for species
* Aleurites
** †Aleurites glandulosa
* †Alismaphyllites
** †Alismaphyllites grandifolius
* †Allantodiopsis
** †Allantoidiopsis erosa
* Fossilized skeleton of the Late Cretaceous-Oligocene Alligator relative Allognathosuchus †Allognathosuchus
** †Allognathosuchus heterodon
** †Allognathosuchus polyodon
** †Allognathosuchus wartheni – type locality for species
* †Allomys
** †Allomys cristabrevis
* †Allophylus
** †Allophylus flexifolia
* Alnus
* †Alphagaulus
** †Alphagaulus vetus
* †Alticonus
** †Alticonus gazini
* †Alveojunctus
** †Alveojunctus minutus
* †Alveugena
** †Alveugena carbonensis – type locality for species
* †Amaramnis
** †Amaramnis gregoryi – type locality for species
* †Ambloctonus
** †Ambloctonus major
** †Ambloctonus priscus – or unidentified comparable form
** †Ambloctonus sinosus
* †Ameiseophis
** †Ameiseophis robinsoni – type locality for species
* †Amelotabes – type locality for genus
** †Amelotabes simpsoni – type locality for species
* Fossilized needles of an Amentotaxus, or catkin-yew Amentotaxus
** †Amentotaxus campbelli
* Amia
** †Amia fragosa
* †Amitabha – type locality for genus
** †Amitabha urbsinterdictensis – type locality for species
* †Ampelopsis
** †Ampelopsis acerifolia
* †Amphechinus
** †Amphechinus ellicottae – type locality for species
* †Amphigyion
** †Amphigyion straitae
* †Amphilemur
* †Amphiplaga
* Amphiuma
** †Amphiuma jepseni – type locality for species
* †Ampliconus
** †Ampliconus antoni – type locality for species
* Assemblage of fossilized skeletons of the softshell turtle Amyda Amyda
** †Amyda egregia – type locality for species
** †Amyda exquisita – type locality for species
** †Amyda mira – type locality for species
* †Amynodon
** †Amynodon advenus
* †Anacardites
** †Anacardites schinoloxus
* Anaclinia – tentative report
* †Anacodon
** †Anacodon nexus – type locality for species
** †Anacodon ursidens
* Anamirta – or unidentified comparable form
** †Anamirta milleri
* †Anaptomorphus
** †Anaptomorphus aemulus – type locality for species
** †Anaptomorphus westi – type locality for species
* Anas
** †Anas acuta
** A living Spatula clypeata, or northern shoveler Anas clypeata
** †Anas crecca
** Anas platyrhynchos
** †Anas schneideri – type locality for species
* †Anatella
** †Anatella tacita – type locality for species
* †Anconodon
** †Anconodon cochranensis
** †Anconodon gidleyi
* †Anemia
** †Anemia elongata
* †Anemorhysis
** †Anemorhysis natronensis – type locality for species
** †Anemorhysis pattersoni – type locality for species
** †Anemorhysis sublettensis – type locality for species
** †Anemorhysis wortmani – type locality for species
* †Anilioides
** †Anilioides nebraskensis
* †Anisonchus
** †Anisonchus sectorius
** †Anisonchus willeyi – type locality for species
* †Ankylodon
** †Ankylodon annectens – or unidentified comparable form
* †Anniealexandria – type locality for genus
** †Anniealexandria gansi – type locality for species
* Anobium
** †Anobium deceptum – type locality for species
** †Anobium lignitum – type locality for species
** †Anobium ovale – type locality for species
* †Anolbanolis – type locality for genus
** †Anolbanolis banalis – type locality for species
** †Anolbanolis geminus – type locality for species
* †Anomoemys
** †Anomoemys lewisi
* Fossilized shell of the Eocene-Oligocene turtle Anosteira †Anosteira
** †Anosteira ornata
** †Anosteira radulina – type locality for species
** †Anosteira trionychoides
* †Antherophagus
** †Antherophagus priscus – type locality for species
* Anthonomus
** †Anthonomus revictus – type locality for species
** †Anthonomus soporus – type locality for species
* †Antiacodon
** †Antiacodon pygmaeus – type locality for species
** †Antiacodon vanvaleni – type locality for species
** †Antiacodon venustus – type locality for species
* A living Antilocapra, or pronghorn Antilocapra
** †Antilocapra americana
* Apalone
** †Apalone extensa – type locality for species
** †Apalone heteroglypta – type locality for species
** †Apalone postera – type locality for species
* †Apatemys
** †Apatemys bellulus – type locality for species
** †Apatemys bellus
** †Apatemys chardini – or unidentified comparable form
** †Apatemys hendryi – type locality for species
** †Apatemys rodens
* †Aphaena
** †Aphaena rotundipennis – type locality for species
* †Apheliscus – type locality for genus
** †Apheliscus chydaeus – type locality for species
** †Apheliscus insidiosus
** †Apheliscus nitidus
** †Apheliscus wapitiensis – type locality for species
* †Aphelops
** †Aphelops megalodus
* †Aphronorus
** †Aphronorus fraudator
** †Aphronorus orieli – type locality for species
** †Aphronorus ratatoski – type locality for species
* †Apodosauriscus – type locality for genus
** †Apodosauriscus minutus – type locality for species
** †Apodosauriscus thermophilus – type locality for species
* †Apriculus
** †Apriculus praeteritus – type locality for species
* †Apternodus
** †Apternodus brevirostris – type locality for species
** †Apternodus dasophylakas – type locality for species
** †Apternodus gregoryi – type locality for species
** †Apternodus iliffensis
** †Apternodus major – type locality for species
* Aquila
** †Aquila antiqua – type locality for species
** A living Aquila chrysaetos, or golden eagle Aquila chrysaetos
* Aralia
** †Aralia notata
** †Aralia serrulata
** †Aralia wrightii
* †Araliophyllum
** †Araliophyllum quina
* Araneus
* †Arapahovius
** †Arapahovius advena – type locality for species
** †Arapahovius gazini – type locality for species
* Araucaria
** †Araucaria longifolia
* †Archaeocyon
** †Archaeocyon falkenbachi
** †Archaeocyon leptodus
* †Archaeolagus
** †Archaeolagus emeraldensis
* Life restoration of the Eocene-Oligocene entelodont mammal Archaeotherium †Archaeotherium
** †Archaeotherium minimus
** †Archaeotherium mortoni
** †Archaeotherium palustris – type locality for species
* †Archaerhineura – type locality for genus
** †Archaerhineura mephitis – type locality for species
* Arcoa
** †Arcoa lindgreni – type locality for species
* †Arctocyon
** †Arctocyon ferox
** †Arctocyon mumak
* †Arctodontomys
** †Arctodontomys nuptus
** †Arctodontomys simplicidens
** †Arctodontomys wilsoni – type locality for species
* Restoration of an Arctodus, or short-faced bear, with a human to scale †Arctodus
** †Arctodus simus
* †Arctostaphylos
** †Arctostaphylos elliptica
* †Arctostylops
** †Arctostylops steini
* †Arecipites
** †Arecipites tenuiexinous
* †Arenahippus
** †Arenahippus aemulor – type locality for species
** †Arenahippus pernix – type locality for species
* †Arfia
** †Arfia junnei
** †Arfia opisthotoma
** †Arfia shoshoniensis
** †Arfia zele – type locality for species
* Aristolochia
** †Aristolochia mortua
* †Armintodelphys
** †Armintodelphys blacki
** †Armintodelphys dawsoni
* †Armintomys
** †Armintomys tullbergi
* †Arpadosaurus – type locality for genus
** †Arpadosaurus gazinorum – type locality for species
** †Arpadosaurus sepulchralis – type locality for species
* †Artimonius
** †Artimonius nocerai
** †Artimonius witteri
* Artocarpus – tentative report
** †Artocarpus quercoides
* †Asarkina
** †Asarkina quadrata – type locality for species
* †Asiabradypus – or unidentified comparable form
* Asio
** †Asio flammeus
** Asio otus
* †Asplenium
** †Asplenium delicatula
** †Asplenium eoligniticum
** †Asplenium eolignitum
** †Asplenium erosum
** †Asplenium iddingsi
** †Asplenium remotidens
* †Astephus
* †Asterotrygon
** An Asterotrygon maloneyi stingray †Asterotrygon maloneyi
* Astronium
** †Astronium truncatum
* †Athyana
** †Athyana balli
* †Aulolithomys
** †Aulolithomys bounites
** †Aulolithomys vexilliames – type locality for species
* †Auroralestes
** †Auroralestes simpsoni
* †Auxontodon
* †Averrhoites
** †Averrhoites affinis
* †Avunculus
** †Avunculus didelphodonti – or unidentified comparable form
* †Axestemys – type locality for genus
** †Axestemys byssina – type locality for species
** †Axestemys cerevisia – type locality for species
** †Axestemys salebrosa – type locality for species
** †Axestemys uintaensis – type locality for species
* †Aycrossia
** †Aycrossia lovei
* Aythya
** Aythya collaris
* Azolla
** †Azolla cretacea
* †Azygonyx
** †Azygonyx ancylion – type locality for species
** †Azygonyx grangeri
** †Azygonyx xenicus – type locality for species

## B

* A
* B
* C
* D
* E
* F
* G
* H
* I
* J
* K
* L
* M
* N
* O
* P
* Q
* R
* S
* T
* U
* V
* W
* X
* Y
* Z
* †Babibasiliscus – type locality for genus
** †Babibasiliscus alxi – type locality for species
* †Baena
** †Baena arenosa – type locality for species
* †Bahndwivici – type locality for genus
** †Bahndwivici ammoskius – type locality for species
* †Baioconodon
** †Baioconodon denverensis – or unidentified comparable form
** †Baioconodon middletoni – type locality for species
** †Baioconodon nordicus
** †Baioconodon wovokae
* †Baiotomeus
** †Baiotomeus douglassi
** †Baiotomeus lamberti
* †Baltemys – type locality for genus
** †Baltemys staurogastros – type locality for species
* †Baptemys
** †Baptemys wyomingensis – type locality for species
* †Barbouromeryx – or unidentified comparable form
* Life restoration of the Paleocene-Eocene pantodont mammal Barylambda †Barylambda
** †Barylambda churchilli – type locality for species
** †Barylambda faberi
* †Bathornis
** †Bathornis fricki – type locality for species
* †Bathygenys
** †Bathygenys alpha
** †Bathygenys hedlundae
* †Bathyopsis
** †Bathyopsis fissidens
* Restorative model of the Eocene shrew-like mammal Batodonoides †Batodonoides
** †Batodonoides vanhouteni – type locality for species
* †Batrachosauroides – tentative report
* Bauhinia
** †Bauhinia wyomingana
** †Bauhinia wyomingiana
* †Beilschmiedia
** †Beilschmiedia eocenica
* †Berchemiopsis
** †Berchemiopsis paucidentata
* †Beringiaphyllum
** †Beringiaphyllum cupanioides
* †Berosus
** †Berosus sexstriatus – type locality for species
** †Berosus tenuis – type locality for species
* †Bessoecetor
** †Bessoecetor septentrionalis
* Betula
** †Betula iddingsi
** †Betula stevensoni
** †Betula stevensonii
* Biomphalaria
* Bison
** A living Bison bison †Bison bison
* †Bisonalveus – type locality for genus
** †Bisonalveus browni – type locality for species
** †Bisonalveus holtzmani – type locality for species
* †Blechnum
** †Blechnum anceps
* Bledius
** †Bledius adamus – type locality for species
** †Bledius faecorum – type locality for species
* †Blickomylus
** †Blickomylus galushai
* Fossilized skeleton of the eocene-?Miocene boa snake Boavus †Boavus – type locality for genus
** †Boavus brevis – type locality for species
** †Boavus idelmani – type locality for species
** †Boavus occidentalis – type locality for species
* Boletina
** †Boletina paludivaga – type locality for species
** †Boletina umbratica – type locality for species
* †Bootherium
** †Bootherium bombifrons
* †Borealosuchus
** †Borealosuchus formidabilis
** †Borealosuchus wilsoni – type locality for species
* †Botauroides – type locality for genus
** †Botauroides parvus – type locality for species
* †Bouromeryx
* †Boverisuchus
** †Boverisuchus vorax
* †Bownomomys – type locality for genus
** †Bownomomys americanus – type locality for species. Formerly known as Teilhardina americana.
** †Bownomomys crassidens – type locality for species. Formerly known as Teilhardina crassidens.
* †Boysia – or unidentified comparable form
** †Boysia phenacodorum
* †Brachianodon
** †Brachianodon westorum – type locality for species
* Restorative portrait of the Miocene oreodont mammal Brachycrus †Brachycrus
** †Brachycrus rusticus
** †Brachycrus sweetwaterensis
** †Brachycrus vaughani
* †Brachyerix
** †Brachyerix macrotis
* †Brachyhyops
** †Brachyhyops viensis
** †Brachyhyops wyomingensis – type locality for species
* †Brachyrhynchocyon
** †Brachyrhynchocyon dodgei
** †Brachyrhynchocyon intermedius
* †Brachyuranochampsa – type locality for genus
** †Brachyuranochampsa eversolei – type locality for species
* Bracon
** †Bracon laminarum – type locality for species
* Branta
** A living Branta canadensis, or Canada goose †Branta canadensis
* †Bridgeremys
** †Bridgeremys pusilla – type locality for species
* †Brontops
* †Browniea
** †Browniea serrata
* †Bryophyte – or unidentified related form
* Bubo
** †Bubo virginianus
* †Bunophorus
** †Bunophorus etsagicus
** †Bunophorus grangeri
** †Bunophorus macropternus
** †Bunophorus robustus
** †Bunophorus sinclairi – type locality for species
* †Bunrsera
** †Bunrsera inaequalateralis
* Buteo
** †Buteo jamaicensis
** †Buteo lagopus
** †Buteo regalis – or unidentified comparable form
* Mounted fossilized skeleton of the Miocene-modern bird of prey Buteogallus Buteogallus

## C

* A
* B
* C
* D
* E
* F
* G
* H
* I
* J
* K
* L
* M
* N
* O
* P
* Q
* R
* S
* T
* U
* V
* W
* X
* Y
* Z
* †Caedocyon
** †Caedocyon tedfordi – type locality for species
* †Caenolambda – type locality for genus
** †Caenolambda jepseni – type locality for species
** †Caenolambda pattersoni – type locality for species
* Life restoration of the Eocene-Oligocene cow-sized rhinoceros Subhyracodon. Charles R. Knight (1890s). †Caenopus
** †Caenopus yoderensis – type locality for species
* †Caesalpinia
** †Caesalpinia flumen-viridensis
** †Caesalpinia pecorae
* †Caesalpinites
** †Caesalpinites falcata – type locality for species
* †Calamagras
** †Calamagras angulatus – or unidentified comparable form
** †Calamagras platyspondyla
** †Calamagras primus – type locality for species
** †Calamagras weigeli
* †Calamospiza
** †Calamospiza melanocorys
* †Calandrites
** †Calandrites cineratius
** †Calandrites defessus
* †Calcardea – type locality for genus
** †Calcardea junnei – type locality for species
* Calidris
** A living Calidris melanotos, or pectoral sandpiper †Calidris melanotos
* †Callomyia
** †Callomyia torporata – type locality for species
* †Callospilopteron – type locality for genus
** †Callospilopteron ocellatum – type locality for species
* †Calycites
** †Calycites ardtunensis
** †Calycites hexaphylla
** †Calycites mikanoides
** †Calycites polysepala
** †Calycites RR58 informal
** †Calycites RR71 informal
* †Camelops
** †Camelops hesternus – or unidentified comparable form
* †Canarium
** †Canarium californicum
* †Canavalia
** †Canavalia diuturna
* Canis
** Modern mounted skeleton of Canis lupus, the grey wolf, to scale with a fossilized skeleton of the Pleistocene wolf Canis dirus, or dire wolf †Canis dirus
** †Canis latrans
** †Canis lupus
* †Cantius
** †Cantius abditus – type locality for species
** †Cantius frugivorus
** †Cantius mckennai
** †Cantius nunienus
** †Cantius ralstoni
** †Cantius simonsi – type locality for species
** †Cantius torresi
** †Cantius trigonodus – type locality for species
* †Capacikala
** †Capacikala parvus – type locality for species
* Capella
** †Capella gallinago
* †Carabites
** †Carabites kincaidi – type locality for species
* Caracara
** A living Caracara plancus, or southern crested caracara †Caracara plancus
* †Cardichelyon – type locality for genus
** †Cardichelyon rogerwoodi – type locality for species
* †Cardiolophus
** †Cardiolophus radinskyi – type locality for species
** †Cardiolophus semihians
* Cardiospermum
** A Cardiospermum coloradensis leaf †Cardiospermum coloradensis
* Carduelis
* †Carpites
** †Carpites newberryana
** †Carpites pedunculatus
** †Carpites verrucosus
* †Carpodaptes
** †Carpodaptes hazelae
** †Carpodaptes hobackensis
** †Carpodaptes jepseni
** †Carpodaptes rosei
** †Carpodaptes stonleyi
* †Carpolestes
** †Carpolestes dubius – type locality for species
** †Carpolestes nigridens
** Life restoration of the Paleocene primate relative Carpolestes simpsoni †Carpolestes simpsoni – type locality for species
* †Carpolithes
** †Carpolithes osseus
* Carya
** †Carya antiquorum
** †Carya veripites
** †Carya viridifluminipites
* Castanea
** †Castanea intermedia
** †Castanea pulchella
* Castor
** †Castor peninsulatus
* †Catopsalis
** †Catopsalis alexanderi
** †Catopsalis calgariensis
* Living Cedrela trees Cedrela
** †Cedrela trainii
* †Cedrelospermum
** †Cedrelospermum lineatum
** †Cedrelospermum nervosum
* †Cedrobaena – type locality for genus
** †Cedrobaena putorius
* †Cedrocherus
** †Cedrocherus aceratus – type locality for species
** †Cedrocherus ryani – type locality for species
* †Cedromus
** †Cedromus wardi
* Foliage and fruit of a living Celastrus, or staff vine †Celastrus
** †Celastrus culveri
** †Celastrus ellipticus
** †Celastrus inaequalis
** †Celastrus winchesteri
* †Celliforma
** †Celliforma spirifer
* Celtis
** †Celtis aspera
** †Celtis newberryi
** †Celtis peracuminata
** †Celtis phenacodorum
* †Centetodon
** †Centetodon bacchanalis
** †Centetodon bembicophagus
** †Centetodon chadronensis
** †Centetodon hendryi
** †Centetodon magnus
** †Centetodon marginalis
** †Centetodon neashami – type locality for species
** †Centetodon patratus
** †Centetodon pulcher
* †Centrinus
** †Centrinus diruptus – type locality for species
* †Centrocercus
** †Centrocercus urophasianus
* †Cephalogale
* †Ceratophyllum
** †Ceratophyllum muricatum
* Life restoration of the Paleocene-Eocene crocodilian Ceratosuchus †Ceratosuchus
** †Ceratosuchus burdoshi
* Cercidiphyllum
** †Cercidiphyllum arcticum
** †Cercidiphyllum articum
** †Cercidiphyllum BB21 informal
** †Cercidiphyllum BB34-52 informal
** †Cercidiphyllum genetrix
** †Cercidiphyllum tiny winged seeds informal
** †Cercidiphyllum tiny wingedseeds informal
* A living Cercopis froghopper †Cercopis
** †Cercopis astricta – type locality for species
* †Cercopites – type locality for genus
** †Cercopites calliscens – type locality for species
** †Cercopites umbratilis – type locality for species
* †Ceutholestes
** †Ceutholestes dolosus
* †Chadrolagus
** †Chadrolagus emryi
* †Chaetoptelea
** †Chaetoptelea microphylla
** †Chaetoptelea pseudofulva – tentative report
* †Chalicomomys
** †Chalicomomys willwoodensis – type locality for species
* Life restoration of the Late Cretaceous-Eocene choristoderan reptile Champsosaurus †Champsosaurus
** †Champsosaurus gigas
* †Chaneya
** †Chaneya tenuis†Chaneya tenuis
* Chara
* Charadrius
** †Charadrius montanus
** †Charadrius vociferus
* Charina
** †Charina prebottae
* Cheilosia
** †Cheilosia ampla – type locality for species
** †Cheilosia scudderi
* †Chelomophrynus – type locality for genus
** †Chelomophrynus bayi – type locality for species
* †Chilostigma – tentative report
** †Chilostigma ostracoderma
* †Chiromyoides
** †Chiromyoides caesor – type locality for species
** †Chiromyoides major – type locality for species
** †Chiromyoides minor – type locality for species
** †Chiromyoides potior
* Chironomus
** †Chironomus septus – type locality for species
* Fossilized skeleton of the Eocene turtle Chisternon †Chisternon
** †Chisternon hebraicum – type locality for species
** †Chisternon undatum – type locality for species
* †Chlororhysis
** †Chlororhysis incomptus – type locality for species
** †Chlororhysis knightensis – type locality for species
* †Choctawius – or unidentified comparable form
* †Cholula
** †Cholula triguttata – type locality for species
* †Choragus
** †Choragus fictilis – type locality for species
* †Chordeiles
** A living Chordeiles minor, or common nighthawk †Chordeiles minor
* †Chriacus
** †Chriacus badgleyi
** †Chriacus baldwini
** †Chriacus gallinae
** †Chriacus katrinae
** †Chriacus oconostotae
** †Chriacus pelvidens
* †Chumashius
* †Cicadula
** †Cicadula saxosa – type locality for species
* †Cimolestes
* †Cinnamomophyllum
** †Cinnamomophyllum RR19 informal
* A living Cinnamomum, or cinnamon tree Cinnamomum
** †Cinnamomum sezannense
** †Cinnamomum spectabilis
* Circus
** †Circus cyaneus
* †Cissites
** †Cissites rocklandensis
* Cissus
** †Cissus haguei
** †Cissus marginata
** †Cissus marginatus
* †Cixius – tentative report
** †Cixius hesperidum – type locality for species
* Flowers of a living Cladrastis, or yellowwood Cladrastis
** †Cladrastis GR579 informal
** †Cladrastis GR580 informal
* †Claenodon
** †Claenodon montanensis
* †Cnemidaria
** †Cnemidaria magna
* †Coccothraustes
** †Coccothraustes vespertinus
* Fruit and foliage of a living Cocculus, or moonseed Cocculus
** †Cocculus flabella
* †Coelidia
** †Coelidia wyomingensis – type locality for species
* Colaptes
** †Colaptes auratus
* †Colodon
** †Colodon woodi
* †Colpocherus
* †Colpoclaenus
** †Colpoclaenus keeferi – type locality for species
** †Colpoclaenus procyonoides – or unidentified comparable form
* Colymbus
** †Colymbus nigricollis
* †Compsemys
** †Compsemys victa
* †Conacodon
** †Conacodon cophater – or unidentified comparable form
** †Conacodon delphae
* Illustration of fossilized vertebrae of the Late Cretaceous-Eocene snake Coniophis. Othniel Charles Marsh (1892). †Coniophis
** †Coniophis carinatus – type locality for species
** †Coniophis platycarinatus – type locality for species
* †Copecion
** †Copecion brachypternus
** †Copecion davisi
* †Copedelphys
** †Copedelphys stevensoni
* †Copelemur
** †Copelemur australotutus – type locality for species
** †Copelemur praetutus
** †Copelemur tutus
* †Copemys
** †Copemys longidens
* †Coriphagus
** †Coriphagus encinensis – or unidentified comparable form
** †Coriphagus montanus
* †Corizus – tentative report
** †Corizus guttatus – type locality for species
* Fossilized skull of the Oligocene-Miocene bone-crushing dog Cormocyon †Cormocyon
** †Cormocyon haydeni
* Cornus
** †Cornus hyperborea
** †Cornus nebrascensis
** †Cornus newberryi
** †Cornus wrightii
* Corvus
** †Corvus brachyrhynchos
** †Corvus corax
* †Corylites
** †Corylites FW01 informal
* †Corylus
** †Corylus insignis
** †Corylus macquarryi
* Corymbites
** †Corymbites velatus – type locality for species
* Life restoration of the Paleocene-Eocene pantodont mammal Coryphodon. Heinrich Harder (1920). †Coryphodon
** †Coryphodon armatus
** †Coryphodon eocaenus
** †Coryphodon lobatus
** †Coryphodon proterus
** †Coryphodon radians
* †Cranea
** †Cranea wyomingensis
* Crataegus
* †Credneria
** †Credneria daturaefolia – tentative report
** †Credneria pachyphylla
* †Cristadjidaumo
** †Cristadjidaumo skinneri – type locality for species
* Crocodylus
** Fossilized skull of the Eocene crocodilian "Crocodylus" affinis †Crocodylus affinis – type locality for species
** †Crocodylus ziphodon – type locality for species
* †Cryptocephalus
** †Cryptocephalus vetustus – type locality for species
* Cryptorhynchus
** †Cryptorhynchus annosus – type locality for species
* Cryptotis
* Culex
** †Culex damnatorum – type locality for species
* †Cupanieidites
** †Cupanieidites inaequalis
** †Cupanieidites inaequatis
* †Cupidinimus
** †Cupidinimus whitlocki
* †Cycadopites
** †Cycadopites follicularis
* Cyclocarya
* †Cyclurus
** †Cyclurus fragosus
* †Cylindrodon
** †Cylindrodon natronensis – type locality for species
** †Cylindrodon solarborus – type locality for species
* Underside of a fossilized cranium of the Oligocene-Miocene bone-crushing dog Cynarctoides †Cynarctoides
** †Cynarctoides acridens
** †Cynarctoides harlowi
** †Cynarctoides luskensis – type locality for species
* †Cyperacites
** †Cyperacites angustior
** †Cyperacites filiferus
** †Cyperacites giganteus
* †Cyriacotherium
** †Cyriacotherium argyreum – type locality for species
** †Cyriacotherium psamminum – type locality for species
* †Cyrilavis
** †Cyrilavis olsoni – type locality for species
* †Cyrtomenus
** †Cyrtomenus concinnus – type locality for species

## D

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* †Dalbergia
* †Daphoenictis
* Life restoration of the Miocene bear-dog Daphoenodon †Daphoenodon
** †Daphoenodon falkenbachi – type locality for species
** †Daphoenodon niobrarensis
** †Daphoenodon skinneri – type locality for species
** †Daphoenodon superbus
* †Daphoenus
** †Daphoenus lambei
* †Dartonius
** †Dartonius jepseni
* A living Dasyatis stingray Dasyatis
* †Davidia
** †Davidia antiqua
* †Dawsonicyon – type locality for genus
** †Dawsonicyon isami – type locality for species
* †Dawsonomys
** †Dawsonomys woodi
* †Dawsonophis – type locality for genus
** †Dawsonophis wyomingensis – type locality for species
* †Debeya
* †Decatoma
** †Decatoma antiqua – type locality for species
* †Delotrochanter
** †Delotrochanter major – type locality for species
* Dendragapus
** A living Dendragapus obscurus, or dusky grouse †Dendragapus obscurus
* †Dendropanax
** †Dendropanax latens
* †Dennstaedia
** †Dennstaedia americana
* †Dennstaedtia
** †Dennstaedtia americana
* †Dennstaedtiopsis
** †Dennstaedtiopsis aerenchymata
* †Desmatippus
** †Desmatippus tyleri
* †Desmatochoerus
** †Desmatochoerus hatcheri
** †Desmatochoerus megalodon
* †Desmatoclaenus
** †Desmatoclaenus mearae
* †Desmatolagus
** †Desmatolagus schizopetrus
* †Desmatotherium
** †Desmatotherium intermedius
* †Desmocyon
** †Desmocyon thomsoni
* †Devallia – tentative report
** †Devallia montana
* †Diacocherus
** †Diacocherus meizon – type locality for species
** †Diacocherus minutus
* Restoration of two of the Eocene even-toed ungulate Diacodexis being hunted by a primitive whale †Diacodexis
** †Diacodexis ilicis
** †Diacodexis kelleyi
** †Diacodexis kellyi
** †Diacodexis metsiacus
** †Diacodexis minutus
** †Diacodexis primus
** †Diacodexis secans
** †Diacodexis woltonensis – type locality for species
* †Diacodon
** †Diacodon celatus
* †Diaplegma
** †Diaplegma obdormitum – type locality for species
* †Diatryma – type locality for genus
** †Diatryma gigantea – type locality for species
* Restoration of the Oligocene-Miocene hornless rhinoceros Diceratherium. Robert Bruce Horsfall (1913). †Diceratherium
** †Diceratherium annectens
** †Diceratherium armatum
** †Diceratherium tridactylum
* Dicotylophyllum
** †Dicotylophyllum anomalum
** †Dicotylophyllum mercerensis
* Dicranomyia
** †Dicranomyia primitiva
** †Dicranomyia rhodolitha – type locality for species
* Dicrostonyx
* †Didelphodontine
* †Didelphodus
** †Didelphodus absarokae
** †Didelphodus altidens
* †Didymictis
** †Didymictis altidens
** †Didymictis leptomylus
** †Didymictis protenus
** †Didymictis proteus
** †Didymictis vancleveae – or unidentified comparable form
* †Dillerlemur
** †Dillerlemur pagei
** †Dillerlemur robinettei – type locality for species
* †Dilophodon
** †Dilophodon destitutus – type locality for species
** †Dilophodon minusculus
* Life restoration of the Eocene-Miocene false saber-toothed cat Dinictis. Robert Bruce Horsfall (1913). †Dinictis
** †Dinictis felina
* †Dinohyus
* †Diospyros
** †Diospyros brachysepala
** †Diospyros haguei
** †Diospyros lamarensis
* †Dipassalus
** †Dipassalus oryctes
* †Diplobunops
** †Diplobunops matthewi
* †Diplocynodon
* †Diplolophus
** †Diplolophus insolens – type locality for species
* Fossilized skeleton of the Early Cretaceous-Eocene bony fish Diplomystus preserved in the act of swallowing another fish †Diplomystus
** †Diplomystus dentatus
* †Dipoides
** †Dipoides stirtoni
* †Dipsalidictis
** †Dipsalidictis aequidens
** †Dipsalidictis krausei – type locality for species
** †Dipsalidictis platypus – type locality for species
** †Dipsalidictis transiens
* †Dipsalodon
** †Dipsalodon churchillorum
** †Dipsalodon matthewi – type locality for species
* Fossilized samara of the Eocene-modern Dipteronia tree Dipteronia
** †Dipteronia GR551 informal
** †Dipteronia insignis
* Discus
* †Dissacus
** †Dissacus argenteus – type locality for species
** †Dissacus longaevus
** †Dissacus navajovius
** †Dissacus praenuntius
* †Distylium
** †Distylium eocenica
* †Dithelysia
** †Dithelysia amorensis
* A living Dolichopus fly Dolichopus
* †Dombeya
** †Dombeya novimundi
* †Domnina
** †Domnina gradata – or unidentified comparable form
* †Domninoides
** †Domninoides valentinensis – or unidentified comparable form
* †Dorraletes
** †Dorraletes diminutivus
* †Douglassciurus
** †Douglassciurus jeffersoni
* †Drimys
* Dryocoetes
** †Dryocoetes carbonarius – type locality for species
** †Dryocoetes impressus
* †Dryomomys – type locality for genus
** †Dryomomys dulcifer – type locality for species
** †Dryomomys szalayi – type locality for species
* Illustration of a modern Dryopteris, or wood fern Dryopteris
** †Dryopteris lakesi
** †Dryopteris longipetiolatum
** †Dryopteris meeteetseana
** †Dryopteris serrata
** †Dryopteris weedii
** †Dryopteris xantholithensis
* †Dunnophis
** †Dunnophis microechinis – type locality for species
** †Dunnophis microechinus
* †Dysagrion – type locality for genus
** †Dysagrion fredericii – type locality for species
** †Dysagrion lakesii – type locality for species
** †Dysagrion packardii – type locality for species

## E

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* Fossilized shell of the Eocene turtle Echmatemys †Echmatemys
** †Echmatemys haydeni
** †Echmatemys lativertebralis
** †Echmatemys megaulax
** †Echmatemys rivalis – type locality for species
** †Echmatemys septaria
** †Echmatemys testudinea
** †Echmatemys wyomingensis
* †Eclytus
** †Eclytus lutatus – type locality for species
* Fossilized skull of the Paleocene-Eocene mammal Ectocion †Ectocion
** †Ectocion cedrus – type locality for species
** †Ectocion collinus – type locality for species
** †Ectocion major – or unidentified comparable form
** †Ectocion mediotuber – type locality for species
** †Ectocion osbornianus
** †Ectocion parvus
** †Ectocion superstes
* †Ectoconus
** †Ectoconus cavigellii – type locality for species
** †Ectoconus ditrigonus
* †Ectoganus
** †Ectoganus bighornensis
** †Ectoganus copei
** †Ectoganus gliriformes
** †Ectoganus gliriformis
** †Ectoganus lobdelli
* †Ectopistes
** Taxidermied male Ectopistes migratorius, or passenger pigeon †Ectopistes migratorius
* †Ectopocynus
** †Ectopocynus antiquus – type locality for species
** †Ectopocynus intermedius – type locality for species
* †Ectypodus
** †Ectypodus aphronorus
** †Ectypodus childei – or unidentified comparable form
** †Ectypodus hazeni – type locality for species
** †Ectypodus laytoni – type locality for species
** †Ectypodus lovei
** †Ectypodus musculus
** †Ectypodus powelli – type locality for species
** †Ectypodus simpsoni
** †Ectypodus szalayi
** †Ectypodus tardus
* †Elaeodendron
** †Elaeodendron polymorphum
* †Ellipsodon
** †Ellipsodon lemuroides – or unidentified comparable form
* †Elphidotarsius
** †Elphidotarsius florencae – or unidentified comparable form
** †Elphidotarsius shotgunensis
* †Elpidophorus
** †Elpidophorus elegans
** †Elpidophorus minor – or unidentified comparable form
* †Elwynella – type locality for genus
** †Elwynella oreas – type locality for species
* †Enhydrocyon
** †Enhydrocyon basilatus
** †Enhydrocyon crassidens
** †Enhydrocyon pahinsintewakpa
* Enochrus
** †Enochrus primaevus – type locality for species
* Life restoration of the Eocene-Oligocene mammal Entelodon. Charles R. Knight. †Entelodon
** †Entelodon coarctatus – or unidentified comparable form
* †Entomolestes – type locality for genus
** †Entomolestes grangeri – type locality for species
** †Entomolestes westgatei – type locality for species
* †Entomophontes – type locality for genus
** †Entomophontes hutchisoni – type locality for species
** †Entomophontes incrustatus – type locality for species
* †Entoptychus
* Life restoration of a pair of the Eocene uintathere mammal Eobasileus. Charles R. Knight (1890s). †Eobasileus
** †Eobasileus cornutus
* †Eobucco
** †Eobucco brodkorbi
* †Eocalopteryx
** †Eocalopteryx atavina – type locality for species
* †Eoceornis – type locality for genus
** †Eoceornis ardetta – type locality for species
* †Eoconodon
** †Eoconodon copanus
* †Eocrex – type locality for genus
** †Eocrex primus – type locality for species
* †Eodiploglossus – type locality for genus
** †Eodiploglossus borealis – type locality for species
* †Eoerianthus
** †Eoerianthus multispinosa
* †Eoformica
** †Eoformica pinguis – type locality for species
* †Eofringillirostrum – type locality for genus
** †Eofringillirostrum boudreauxi – type locality for species
* †Eoglyptosaurus
** †Eoglyptosaurus donohoei – type locality for species
* Eohiodon
* Life restoration of the Eocene horse Eohippus. Heinrich Harder (1920). †Eohippus
** †Eohippus cristatus
* †Eoictops – type locality for genus
** †Eoictops novaceki – type locality for species
* †Eoliarus – tentative report
** †Eoliarus lutensis – type locality for species
* †Eomoropus
** †Eomoropus amarorum
** †Eomoropus anarsius
* †Eopodagrion – type locality for genus
** †Eopodagrion abortivum – type locality for species
** †Eopodagrion scudderi – type locality for species
* †Eorhinophrynus
** †Eorhinophrynus septentrionalis – type locality for species
* †Eoryctes – type locality for genus
** †Eoryctes melanus – type locality for species
* †Eostangeria
** †Eostangeria pseudopteris
* †Eostrix
** †Eostrix martinellii – type locality for species
* Life restoration of the Eocene brontothere mammal Eotitanops †Eotitanops
** †Eotitanops borealis
* †Eotylopus
** †Eotylopus reedi – type locality for species
* †Eozygodactylus – type locality for genus
** †Eozygodactylus americanus – type locality for species
* †Epicaerus
** †Epicaerus dilapsus – type locality for species
** †Epicaerus effossus – type locality for species
** †Epicaerus exanimis – type locality for species
** †Epicaerus fodinarum
** †Epicaerus saxatilis – type locality for species
** †Epicaerus subterraneus
** †Epicaerus terrosus – type locality for species
* Underside of the fossilized cranium of the Eocene horse Epihippus †Epihippus
** †Epihippus gracilis
* †Epitriplopus
** †Epitriplopus uintensis
* †Epoicotherium
** †Epoicotherium unicum
* †Equisetum
** †Equisetum canaliculatum
** †Equisetum deciduum
** †Equisetum FW21 informal
** †Equisetum haguei
* Equus
** †Equus conversidens
* Eremophila
** †Eremophila alpestris
* Erythrina speciosa inflorescences, Brazil Erythrina
** †Erythrina roanensis – type locality for species
* Esox
** †Esox kronneri – type locality for species
* †Esthonyx
** †Esthonyx acutidens
** †Esthonyx bisulcatus
** †Esthonyx gunnelli
** †Esthonyx spatularius
* †Eucastor
* †Eucommia
** †Eucommia serrata
* †Eudaemonema
** †Eudaemonema cuspidata
* Branches and fruits of a living Eugenia Eugenia
** †Eugenia americana
* †Eugnamptus
** †Eugnamptus decemsatus – type locality for species
** †Eugnamptus grandaevus
* †Euhapsis
** †Euhapsis ellicottae
* †Eumys
** †Eumys elegans
* †Euparius
** †Euparius elusus – type locality for species
** †Euparius repertus – type locality for species
* Euphagus
** †Euphagus cyanocephalus
** †Euphagus magnirostris
* †Euproteaciphyllum
** †Euproteaciphyllum minutum
* Fossilized mandible of the Eocene-Oligocene false saber-toothed cat Eusmilus †Eusmilus
** †Eusmilus sicarius
* Eutamias
* †Eutypomys
** †Eutypomys parvus
* †Exostinus
** †Exostinus lancensis – or unidentified comparable form

## F

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* Fagus
** †Fagus antipofii
** †Fagus undulata
* Falco
** †Falco columbarius
** †Falco falconella – type locality for species
** A living Falco mexicanus, or prairie falcon †Falco mexicanus
** †Falco rusticolus
** †Falco sparverius
* †Ficarasites – type locality for genus
** †Ficarasites stigmaticum – type locality for species
* Ficus
** †Ficus affinis
** †Ficus artocarpoides
** †Ficus asiminaefolia
** †Ficus deformata
** †Ficus densifolia
** †Ficus haguei
** †Ficus planicostata
** †Ficus shastensis – tentative report
** †Ficus subtruncata
** †Ficus tiliaefolia – tentative report
** †Ficus ungeri
* †Firmianites – type locality for genus
** †Firmianites aterrimus – type locality for species
* †Florentiamys
** †Florentiamys kinseyi – type locality for species
** †Florentiamys loomisi – type locality for species
* Fossilized skeleton of the Eocene bird Fluvioviridavis †Fluvioviridavis – type locality for genus
** †Fluvioviridavis platyrhamphus – type locality for species
* †Foekenia
** †Foekenia catenulata
* †Fortuna
** †Fortuna marsilioides – or unidentified comparable form
* †Franimys
** †Franimys ambos
** †Franimys amherstensis – type locality for species
** †Franimys buccatus
* †Fraxinoipollenis
** †Fraxinoipollenis variabilis
* †Fraxinoipollenites
** †Fraxinoipollenites pachyexinous
** †Fraxinoipollenites variabilis
* †Fraxinopollenites
** †Fraxinopollenites variabilis
* Illustrations of the flowers and foliage of a living Fraxinus, or ash tree, with insets further detailing its anatomy †Fraxinus
** †Fraxinus eocenica
** †Fraxinus eocinica
** †Fraxinus wrightii
* †Fulgora
** †Fulgora granulosa – type locality for species
** †Fulgora populata – type locality for species

## G

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* †Gagadon
** †Gagadon minimonstrum
* †Galbreathia
** †Galbreathia novellus
* †Galecyon
** †Galecyon mordax
* Galerita
** †Galerita marshii – type locality for species
* Fossilized skeleton of the Eocene bird Gallinuloides †Gallinuloides – type locality for genus
** †Gallinuloides wyomingensis – type locality for species
* Gastrocopta
* Gastrodonta
* †Gaultia – type locality for genus
** †Gaultia silvaticus – type locality for species
* †Gazinius
** †Gazinius amplus
** †Gazinius bowni – type locality for species
* †Gazinocyon
** †Gazinocyon vulpeculus
* †Gelastops
** †Gelastops joni – type locality for species
** †Gelastops parcus
* †Geranoides – type locality for genus
** †Geranoides jepseni – type locality for species
* †Geringophis
** †Geringophis depressus
* Gerrhonotus – or unidentified comparable form
* Ginkgo
** Restored foliage of the Late Cretaceous-Miocene ginkgo tree Ginkgo adiantoides †Ginkgo adiantoides
* †Gleditsia – or unidentified related form
** †Gleditsia RR29 informal
* †Gleicheniidites
* †Glypta
** †Glypta transversalis – type locality for species
* †Glyptosaurus – type locality for genus
** †Glyptosaurus agmodon – type locality for species
** †Glyptosaurus obtusidens – type locality for species
** †Glyptosaurus rhodinos – type locality for species
** †Glyptosaurus sphenodon – type locality for species
** †Glyptosaurus sylvestris – type locality for species
* Glyptostrobus
** Fossilized foliage of the Early Cretaceous-Pleistocene conifer Glyptostrobus europaeus †Glyptostrobus europaeus
** †Glyptostrobus nordenskioldi
* †Goinophis – tentative report
* †Gomphochelys – type locality for genus
** †Gomphochelys nanus – type locality for species
* †Goniacodon
** †Goniacodon levisanus – type locality for species
* †Goniodontomys
** †Goniodontomys disjunctus
* Gopherus
** †Gopherus laticuneus
* †Gracilocyon
** †Gracilocyon rosei
** †Gracilocyon winkleri
* †Grangerella
* †Gregorymys
** †Gregorymys formosus
** †Gregorymys riggsi – type locality for species
* †Grewiopsis – tentative report
** †Grewiopsis aldersoni
* †Griphomys
* Grus
** †Grus canadensis
** †Grus marshi – type locality for species
* Gulo
** A living Gulo gulo, or wolverine †Gulo gulo
* †Gymnetron
** †Gymnetron lecontei – type locality for species
* †Gymnocladus
** †Gymnocladus hesperia
* Gyraulus – or unidentified comparable form

## H

* A
* B
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* F
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* H
* I
* J
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* L
* M
* N
* O
* P
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* T
* U
* V
* W
* X
* Y
* Z
* †Habrosaurus
** †Habrosaurus dilatus
* †Hadrianus
** †Hadrianus allabiatus – type locality for species
** †Hadrianus quadratus – type locality for species
* †Hammapteryx – type locality for genus
** †Hammapteryx reticulata – type locality for species
* Restoration of the Paleocene-Eocene mesonychian mammal Hapalodectes †Hapalodectes
** †Hapalodectes anthracinus
** †Hapalodectes leptognathus
* †Hapalorestes
** †Hapalorestes lovei – type locality for species
* †Haplaletes
** †Haplaletes disceptatrix
** †Haplaletes pelicatus – type locality for species
* †Haploconus
* †Haplodontosaurus
** †Haplodontosaurus excedens
* †Haplolambda
** †Haplolambda quinni
* †Haplomylus
** †Haplomylus bozemanensis – type locality for species
** †Haplomylus palustris
** †Haplomylus scottianus – type locality for species
** †Haplomylus simpsoni
** †Haplomylus speirianus
** †Haplomylus zalmouti
* Fossilized skull of the mesonychian mammal Harpagolestes †Harpagolestes
** †Harpagolestes macrocephalus – type locality for species
* †Harpalodon
** †Harpalodon sylvestris – or unidentified comparable form
* †Harrymys
** †Harrymys irvini
** †Harrymys woodi
* †Helaletes – type locality for genus
** †Helaletes nanus – type locality for species
* †Heliscomys
** †Heliscomys hatcheri
** †Heliscomys mcgrewi
** †Heliscomys ostranderi
** †Heliscomys vetus – or unidentified comparable form
* †Helix
** †Helix evanstonensis
** †Helix sinclairi
* Fossilized skull of the Oligocene lizard Helodermoides †Helodermoides
** †Helodermoides tuberculatus
* †Helohyus
** †Helohyus lentus
** †Helohyus milleri – type locality for species
** †Helohyus plicodon – type locality for species
* †Hemiacodon
** †Hemiacodon casamissus – type locality for species
** †Hemiacodon engardae – type locality for species
** †Hemiacodon gracilis
* Fossilized lower jaw of the Miocene-Pleistocene llama relative Hemiauchenia †Hemiauchenia
* †Hemipsalodon
** †Hemipsalodon grandis
* Hemitelia
** †Hemitelia magna
* †Hemithlaeus
** †Hemithlaeus harbourae
** †Hemithlaeus josephi
* †Hendryomeryx
** †Hendryomeryx wilsoni
* †Heptacodon
* †Heptodon
** †Heptodon calciculus
** †Heptodon posticus
* Life restoration of the Eocene-Miocene mammal Herpetotherium †Herpetotherium
** †Herpetotherium innominatum – type locality for species
** †Herpetotherium knighti
** †Herpetotherium youngi – or unidentified comparable form
* †Hesperocyon
** †Hesperocyon gregarius
* †Hesperopetes
** †Hesperopetes thoringtoni – type locality for species
* †Hesperosorex
** †Hesperosorex lovei – type locality for species
* †Heteraletes
** †Heteraletes leotanus
* †Hexacodus
** †Hexacodus pelodes
** †Hexacodus uintensis
* †Hicoria
** †Hicoria antiqua
** †Hicoria crescentia
** †Hicoria culveri
* Hirundo – or unidentified comparable form
** †Hirundo pyrrhonota
* †Holospira
* †Homacodon
** †Homacodon vagans – type locality for species
* †Homalota
** †Homalota recisa – type locality for species
* †Homogalax
** †Homogalax protapirinus
* †Honrovits – type locality for genus
** †Honrovits tsuwape – type locality for species
* Life restoration of the Eocene-Oligocene false saber-toothed cat Hoplophoneus. Robert Bruce Horsfall (1913). †Hoplophoneus
** †Hoplophoneus mentalis
** †Hoplophoneus primaevus
* †Hovenia
** †Hovenia oregonensis – or unidentified comparable form
* †Huerfanodon
** †Huerfanodon polecatensis – type locality for species
* †Hummelichelys
** †Hummelichelys annae – type locality for species
** †Hummelichelys ellipticus
** †Hummelichelys grangeri – type locality for species
** †Hummelichelys guttatus – type locality for species
* †Hutchemys
** †Hutchemys rememdium
* Life restoration of the Eocene-Miocene creodont mammal Hyaenodon †Hyaenodon
** †Hyaenodon crucians
** †Hyaenodon horridus
** †Hyaenodon megaloides
** †Hyaenodon montanus
** †Hyaenodon mustelinus
** †Hyaenodon venturae
** †Hyaenodon vetus
* Hydrangea
** †Hydrangea antica
** †Hydrangea GR537 informal
* Hydrobia – report made of unidentified related form or using admittedly obsolete nomenclature
* A living Hydrobius water scavenger beetle Hydrobius
** †Hydrobius confixus – type locality for species
** †Hydrobius decineratus – type locality for species
* †Hydrochus
** †Hydrochus relictus – type locality for species
* †Hydromystria
** †Hydromystria expansa
* †Hylobius
** †Hylobius packardii – type locality for species
** †Hylobius provectus – type locality for species
* Life restoration of the Eocene odd-toed ungulate Hyopsodus †Hyopsodus
** †Hyopsodus aemulor
** †Hyopsodus latidens
** †Hyopsodus lepidus – type locality for species
** †Hyopsodus loomisi
** †Hyopsodus lysitensis
** †Hyopsodus mentalis
** †Hyopsodus minor
** †Hyopsodus minusculus – type locality for species
** †Hyopsodus miticulus
** †Hyopsodus paulus – type locality for species
** †Hyopsodus pauxillus – type locality for species
** †Hyopsodus powellianus
** †Hyopsodus simplex
** †Hyopsodus tonksi – type locality for species
** †Hyopsodus uintensis
** †Hyopsodus walcottianus
** †Hyopsodus wortmani
* †Hypertragulus
** †Hypertragulus calcaratus
* †Hypisodus
** †Hypisodus alacer
** †Hypisodus minimus
* Life restoration of the Miocene horse Hypohippus. Heinrich Harder (1920). †Hypohippus
** †Hypohippus affinis
* †Hypolagus
** †Hypolagus parviplicatus – or unidentified comparable form
* †Hyporhina
** †Hyporhina tertia
* †Hypsiops
** †Hypsiops breviceps
* †Hyrachyus
** †Hyrachyus eximius
** †Hyrachyus modestus – type locality for species
* Life restoration of the Eocene-Oligocene odd-toed ungulate Hyracodon. Charles R. Knight (1896). †Hyracodon
** †Hyracodon nebraskensis
** †Hyracodon petersoni
** †Hyracodon priscidens
* †Hyracotherium
** †Hyracotherium vasacciense

## I

* A
* B
* C
* D
* E
* F
* G
* H
* I
* J
* K
* L
* M
* N
* O
* P
* Q
* R
* S
* T
* U
* V
* W
* X
* Y
* Z
* Fossilized skeleton of the Eocene bat Icaronycteris †Icaronycteris – type locality for genus
** †Icaronycteris index – type locality for species
* †Ignacius
** †Ignacius clarkforkensis – type locality for species
** †Ignacius fremontensis
** †Ignacius frugivorus
** †Ignacius graybullianus
* †Iguanavus – type locality for genus
** †Iguanavus exilis – type locality for species
* †Indusia
** †Indusia calculosa – type locality for species
* †Insulapollenites
** †Insulapollenites leboensis
** †Insulapollenites rugulatus
* †Intyrictis
** †Intyrictis vanvaleni
* †Iridodon – type locality for genus
** †Iridodon datzae – type locality for species
* Mounted fossilized skeleton of the Eocene-Oligocene rodent Ischyromys†Ischyromys
** †Ischyromys typus
** †Ischyromys veterior
* †Isectolophus
** †Isectolophus latidens
** †Isectolophus radinskyi – type locality for species
* †Isoetites
** †Isoetites horridus
* †Iulus
** †Iulus telluster – type locality for species

## J

* A
* B
* C
* D
* E
* F
* G
* H
* I
* J
* K
* L
* M
* N
* O
* P
* Q
* R
* S
* T
* U
* V
* W
* X
* Y
* Z
* †Jepsenella
** †Jepsenella praepropera
* †Jepsibaena
** †Jepsibaena minor – type locality for species
* †Joffrea
** †Joffrea BB20 informal
** †Joffrea FW50 informal
* †Judithemys
** †Judithemys backmani – or unidentified comparable form
* †Juglandicarya
* †Juglandiphyllites
** †Juglandiphyllites glabra
* Juglans
** †Juglans crescentia
** †Juglans laurifolia
** †Juglans rugosa
** †Juglans schimperi
* Fossilized skeleton of the Eocene wading bird Juncitarsus †Juncitarsus – type locality for genus
** †Juncitarsus gracillimus – type locality for species
* Junco – or unidentified comparable form
** †Junco hyemalis
* †Junglandaceae

## K

* A
* B
* C
* D
* E
* F
* G
* H
* I
* J
* K
* L
* M
* N
* O
* P
* Q
* R
* S
* T
* U
* V
* W
* X
* Y
* Z
* †Kalmia
** †Kalmia elliptica
* †Kalobatippus
** †Kalobatippus agatensis
** †Kalobatippus avus
* Fossilized skeleton of the Eocene bony fish Knightia †Knightia
** †Knightia eocaena
* †Knightomys
** †Knightomys cremneus
** †Knightomys cuspidatus
** †Knightomys depressus
** †Knightomys huerfanensis
** †Knightomys minor
** †Knightomys senior
* Koelreuteria
** †Koelreuteria viridifluminis
* †Koniaryctes
** †Koniaryctes paulus – type locality for species
* †Kydia – or unidentified related form
** †Kydia FW61 informal

## L

* A
* B
* C
* D
* E
* F
* G
* H
* I
* J
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* L
* M
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* O
* P
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* R
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* T
* U
* V
* W
* X
* Y
* Z
* †Labidolemur
** †Labidolemur kayi
** †Labidolemur major – type locality for species
** †Labidolemur serus
** †Labidolemur soricoides
* Laccobius
** †Laccobius elongatus – type locality for species
* †Laevigatosporites
* A living Lagopus, or ptarmigan †Lagopus
** †Lagopus leucurus – or unidentified comparable form
* †Lambdotherium
** †Lambdotherium popoagicum
* †Lambertocyon
** †Lambertocyon eximius
** †Lambertocyon gingerichi – type locality for species
* Lanius
** †Lanius ludovicianus
* Larus – or unidentified comparable form
* †Lastrea
** †Lastrea goldiana
* Lathrobium
** †Lathrobium abscessum – type locality for species
* †Laurinoxylon
** †Laurinoxylon pulchellum
* †Laurophyllum
** †Laurophyllum caudatum
** †Laurophyllum perseanum
* Living Laurus, or laurel trees Laurus
** †Laurus californica
** †Laurus grandis
** †Laurus montana
** †Laurus perdita
** †Laurus primigenia – tentative report
** †Laurus princeps
** †Laurus socialis
* †Leguminosites
** †Leguminosites coloradensis
** †Leguminosites lamarensis
** †Leguminosites lesquereuxiana
** †Leguminosites regularis – type locality for species
* Leiocephalus
* †Leipsanolestes
** †Leipsanolestes siegfriedti
* Illustration of a living Lepisosteus, or gar Lepisosteus
** †Lepisosteus glaber – or unidentified comparable form
** †Lepisosteus occidentalis
* †Leptacodon
** †Leptacodon donkroni
** †Leptacodon munusculum
** †Leptacodon packi – type locality for species
** †Leptacodon tener
* †Leptarctus – or unidentified comparable form
* Restoration of the Oligocene-Miocene oreodont mammal Leptauchenia †Leptauchenia
** †Leptauchenia decora
** †Leptauchenia major
* †Leptictis
** †Leptictis dakotensis
* †Leptocyon
** †Leptocyon gregorii
* †Leptolambda
** †Leptolambda schmidti
* Life restoration of the Eocene-Oligocene even-toed ungulate Leptomeryx †Leptomeryx
** †Leptomeryx esulcatus
** †Leptomeryx evansi
** †Leptomeryx mammifer
** †Leptomeryx semicinctus
** †Leptomeryx speciosus
** †Leptomeryx yoderi – type locality for species
* †Leptoreodon
* †Leptotomus
** †Leptotomus guildayi
** †Leptotomus parvus – type locality for species
* †Leptotragulus
** †Leptotragulus clarki – or unidentified comparable form
** †Leptotragulus medius
** †Leptotragulus ultimus
* Lepus
* Lepyrus – tentative report
** †Lepyrus evictus – type locality for species
* †Lestophis
** †Lestophis anceps – type locality for species
** †Lestophis crassus – type locality for species
* †Leucosticte
** †Leucosticte arctoa
* †Limaconyssus – type locality for genus
** †Limaconyssus habrus – type locality for species
* †Limalophus
** †Limalophus compositus
** †Limalophus contractus – type locality for species
* Top view of a fossilized skull of the Eocene creodont mammal Limnocyon †Limnocyon
** †Limnocyon cuspidens – type locality for species
** †Limnocyon medius
** †Limnocyon potens – type locality for species
** †Limnocyon velox – type locality for species
** †Limnocyon verus – type locality for species
* †Limnoecus
* Fossilized skeleton of the Eocene freshwater frigatebird Limnofregata †Limnofregata – type locality for genus
** †Limnofregata azygosternon – type locality for species
** †Limnofregata hutchisoni – type locality for species
* Lindera
** †Lindera obtusata
** †Lindera varifolia – type locality for species
* †Lisserpeton
** †Lisserpeton bairdi
* †Listronotus
** †Listronotus muratus – type locality for species
* †Litaletes
** †Litaletes disjunctus
** †Litaletes ondolinde
* †Lithexorista – type locality for genus
** †Lithexorista scudderi – type locality for species
* †Lithohypoderma
** A Lithohypoderma ascarides larva †Lithohypoderma ascarides - type locality for species
* †Lithophis – type locality for genus
** †Lithophis sargenti – type locality for species
* †Lithophysa – type locality for genus
** †Lithophysa tumulta – type locality for species
* †Lithopsis – type locality for genus
** †Lithopsis elongata – type locality for species
** †Lithopsis fimbriata – type locality for species
* Life restoration of the Paleocene-Eocene bird Lithornis †Lithornis
** †Lithornis plebius – type locality for species
** †Lithornis promiscuus – type locality for species
* †Lithotorus – type locality for genus
** †Lithotorus cressoni – type locality for species
* †Litocherus
** †Litocherus lacunatus – type locality for species
** †Litocherus notissimus
** †Litocherus zygeus – type locality for species
* †Litolagus
** †Litolagus molidens
* †Litolestes
** †Litolestes ignotus – type locality for species
* †Litomylus
** †Litomylus dissentaneus – type locality for species
** †Litomylus ishami – type locality for species
** †Litomylus scaphicus – type locality for species
* †Litoyoderimys
** †Litoyoderimys auogoleus
* †Lophiotherium
** †Lophiotherium vasacciensis – type locality for species
* †Lophiparamys
** †Lophiparamys debequensis
** †Lophiparamys murinus
** †Lophiparamys woodi
* †Lophocion
** †Lophocion grangeri – type locality for species
* †Loveina – type locality for genus
** †Loveina minuta
** †Loveina sheai
** †Loveina wapitiensis
** †Loveina zephyri – type locality for species
* †Loxolophus
** †Loxolophus criswelli
** †Loxolophus faulkneri – type locality for species
** †Loxolophus hyattianus – or unidentified comparable form
** †Loxolophus priscus
* †Lucashyus – type locality for genus
** †Lucashyus coombsae – type locality for species
* †Lyctocoris – tentative report
** †Lyctocoris terreus – type locality for species
* Lygodium
** †Lygodium coloradense
** †Lygodium kaulfussi
* Lynx
** A living Lynx lynx, or Eurasian lynx †Lynx lynx – tentative report
* †Lystra – tentative report
** †Lystra leei – type locality for species
** †Lystra richardsoni – type locality for species

## M

* A
* B
* C
* D
* E
* F
* G
* H
* I
* J
* K
* L
* M
* N
* O
* P
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* T
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* X
* Y
* Z
* †Maceopolipollenites
** †Maceopolipollenites amplus
** †Maceopolipollenites leboensis
** †Maceopolipollenites rotundus
** †Maceopolipollenites tenuipolus
** †Maceopolipollenites triorbicularis
* †Macginitiea
** †Macginitiea gracilis
** †Macginitiea wyomingensis
* †Machaeroides
** †Machaeroides eothen
** †Machaeroides simpsoni – type locality for species
* †Machaerosaurus
** †Machaerosaurus torrejonensis
* Macrocranion
** †Macrocranion junnei – type locality for species
** †Macrocranion nitens
** †Macrocranion robinsoni
* †Macrotarsius
** †Macrotarsius siegerti – type locality for species
* Close-up view of a Magnolia flower Magnolia
** †Magnolia borealis
** †Magnolia californica
** †Magnolia culveri
** †Magnolia magnifica
** †Magnolia magnifolia
** †Magnolia microphylla
** †Magnolia pollardi
** †Magnolia spectabilis
* †Maiorana
** †Maiorana ferrisensis – type locality for species
** †Maiorana noctiluca
* †Malapoenna
** †Malapoenna cuneata
** †Malapoenna lamarensis
* †Malaquiferus
** †Malaquiferus tourteloti – type locality for species
* †Malfelis – type locality for genus
** †Malfelis badwaterensis – type locality for species
* †Mammacyon
** †Mammacyon ferocior – type locality for species
* †Mammuthus
** Life restoration of a herd of Mammuthus columbi, or Columbian mammoths. The extent of the fur depicted is hypothetical. Charles R. Knight (1909). †Mammuthus columbi
* Marmota
* †Marsholestes
** †Marsholestes dasypelix – type locality for species
* †Mattimys
** †Mattimys kalicola
* †Megacerops
** †Megacerops osborni – type locality for species
* †Megadelphus
** †Megadelphus lundeliusi
* †Megalagus
** †Megalagus brachyodon
** †Megalagus primitivus
** †Megalagus turgidus
* †Megalesthonyx
** †Megalesthonyx hopsoni
* Restorative portrait, reconstructed skull, and actual fossil of the Miocene weasel relative Megalictis †Megalictis
** †Megalictis ferox
** †Megalictis petersoni
* †Melanosaurus – type locality for genus
** †Melanosaurus maximus – type locality for species
* †Melastomites
** †Melastomites montanensis
* †Meliakrouniomys
** †Meliakrouniomys skinneri
* †Meliosma
** †Meliosma flexuosa
** †Meliosma longifolia
* Life restoration of the Eocene mammal Meniscotherium. Robert Bruce Horsfall (1913). †Meniscotherium
** †Meniscotherium chamense
** †Meniscotherium priscum
** †Meniscotherium tapiacetum
** †Meniscotherium tapiacitum
* †Menisperimites
** †Menisperimites parvareolatus
* †Menispermites
** †Menispermites limacioides – type locality for species
** †Menispermites parvareolatus
* Life restoration of the Miocene rhinoceros Menoceras †Menoceras
** †Menoceras arikarense
** †Menoceras barbouri
* †Menops
** †Menops heloceras
** †Menops marshi – or unidentified comparable form
* †Mentoclaenodon
** †Mentoclaenodon acrogenius – type locality for species
* Mergus
** †Mergus merganser
* Life restoration of the Miocene three-toed horse Merychippus †Merychippus
** †Merychippus coloradense
** †Merychippus insignis – or unidentified comparable form
** †Merychippus primus
* †Merychyus
** †Merychyus arenarum
** †Merychyus crabilli
** †Merychyus elegans – or unidentified comparable form
** †Merychyus minimus
* †Merycobunodon – tentative report
** †Merycobunodon walshi – type locality for species
* †Merycochoerus
** †Merycochoerus chelydra
** †Merycochoerus magnus
** †Merycochoerus matthewi
* Mounted fossilized skeleton of the Miocene pronghorn Merycodus †Merycodus
** †Merycodus sabulonis – or unidentified comparable form
** †Merycodus warreni – or unidentified comparable form
* †Merycoides
** †Merycoides longiceps
** †Merycoides pariogonus
* †Merycoidodon
** †Merycoidodon culbertsoni – type locality for species
** †Merycoidodon major
** †Merycoidodon presidioensis – or unidentified comparable form
* †Mesatirhinus
** †Mesatirhinus megarhinus
* †Mesocyon – report made of unidentified related form or using admittedly obsolete nomenclature
** †Mesocyon temnodon
* †Mesodma
** †Mesodma ambigua – type locality for species
** †Mesodma formosa
** †Mesodma garfieldensis – or unidentified comparable form
** †Mesodma hensleighi
** †Mesodma pygmaea
* Life restoration of the Eocene-Oligocene horse Mesohippus. Heinrich Harder (c. 1920). †Mesohippus
** †Mesohippus bairdi
** †Mesohippus westoni – or unidentified comparable form
* †Mesomeryx – or unidentified comparable form
** †Mesomeryx grangeri
* †Mesonyx
** †Mesonyx obtusidens – type locality for species
* †Mesoreodon
** †Mesoreodon chelonyx
** †Mesoreodon minor – type locality for species
* †Mesoscalops
** †Mesoscalops scopelotemos
* Life restoration of the Eocene pangolin relative Metacheiromys †Metacheiromys
** †Metacheiromys dasypus – type locality for species
** †Metacheiromys marshi – type locality for species
* †Metadjidaumo
** †Metadjidaumo hendryi – type locality for species
* †Metamynodon
** †Metamynodon planifrons – or unidentified comparable form
* †Metanoiamys
** †Metanoiamys paradoxus
* †Metarhinus
* Metasequoia
** †Metasequoia occidentalis
* †Metatomarctus
** †Metatomarctus canavus
* Life restoration of the Paleocene-Eocene mammal Miacis †Miacis
** †Miacis deutschi
** †Miacis exiguus
** †Miacis latidens
** †Miacis medius
** †Miacis parvivorus – type locality for species
** †Miacis petilus
** †Miacis vorax
* †Michenia
* Micrasema – tentative report
** †Micrasema tessellatum – type locality for species
* †Microclaenodon
** †Microclaenodon assurgens
* †Microcosmodon
** †Microcosmodon conus – type locality for species
** †Microcosmodon rosei – type locality for species
* †Micromomys
** †Micromomys antelucanus
** †Micromomys silvercouleei – type locality for species
* †Microparamys
** †Microparamys cheradius
** †Microparamys dubius
** †Microparamys hunterae
** †Microparamys minutus
* Illustration of the shell in multiple views of a living Microphysula land snail Microphysula – or unidentified comparable form
* †Micropternodus
** †Micropternodus borealis
* †Microsus
** †Microsus cuspidatus – type locality for species
* †Microsyops
** †Microsyops angustidens – type locality for species
** †Microsyops annectens
** †Microsyops cardiorestes
** †Microsyops elegans – type locality for species
** †Microsyops knightensis
** †Microsyops latidens
** †Microsyops scottianus
* Microtus
** A living Microtus pennsylvanicus, or meadow vole †Microtus pennsylvanicus
* Mictomys
** †Mictomys vetus
* †Mimatuta
** †Mimatuta makpialutae
** †Mimatuta minuial – type locality for species
* †Mimetodon
** †Mimetodon churchilli – type locality for species
** †Mimetodon silberlingi
* †Mimoperadectes
** †Mimoperadectes houdei – type locality for species
** †Mimoperadectes labrus – type locality for species
* †Mimosites
** †Mimosites coloradensis
* †Mimotricentes
** †Mimotricentes fremontensis – type locality for species
* Life restoration of the Eocene-Oligocene oreodont mammal Miniochoerus †Miniochoerus
** †Miniochoerus affinis – type locality for species
** †Miniochoerus chadronensis – type locality for species
** †Miniochoerus forsythae
** †Miniochoerus gracilis
* †Minippus
** †Minippus index
* †Mioclaenus
** †Mioclaenus opisthacus – or unidentified comparable form
** †Mioclaenus turgidus
* †Miocyon
** †Miocyon major – or unidentified comparable form
* †Mioheteromys
** †Mioheteromys amplissimus
* †Miohippus
** †Miohippus obliquidens
* †Miolabis
** †Miolabis fissidens
* †Miomustela
* Fossilized skeleton of the Eocene perch relative Mioplosus †Mioplosus
* †Miospermophilus
** †Miospermophilus wyomingensis
* †Miotapirus
** †Miotapirus harrisonensis – type locality for species
* †Miotylopus
** †Miotylopus gibbi
** †Miotylopus leonardi
** †Miotylopus taylori – type locality for species
* Restoration of the Pliocene-Pleistocene Miracinonyx, or American cheetah †Miracinonyx
** †Miracinonyx studeri
* †Mithrandir
** †Mithrandir gillianus
* †Mitostylus
** †Mitostylus seculorum – type locality for species
* †Mixodectes
** †Mixodectes malaris
* Mnemosyne
** †Mnemosyne terrentula – type locality for species
* †Mojavemys
** †Mojavemys magnumarcus
* †Monosaulax
** †Monosaulax curtus – or unidentified comparable form
* †Moropus
** †Moropus hollandi
* Morus
** †Morus montanensis
* †Musophyllum
** †Musophyllum complicatum
* Mustela
** †Mustela americana
** †Mustela nigripes
* Mycetobia – tentative report
** †Mycetobia terricola – type locality for species
* †Mylanodon – type locality for genus
** †Mylanodon rosei – type locality for species
* Fruit of a living Myrica, or firetree Myrica
** †Myrica lamarensis
** †Myrica scottii
** †Myrica wardii
* †Myrmecoboides
** †Myrmecoboides montanensis
* Myrmica
* †Myrtophyllum
** †Myrtophyllum torreyi
* †Mysops
** †Mysops fraternus
** †Mysops minimus – type locality for species
** †Mysops parvus – type locality for species
* †Mytonolagus
** †Mytonolagus petersoni
** †Mytonolagus wyomingensis – type locality for species
* †Mytonomys
** †Mytonomys coloradensis
** †Mytonomys wortmani

## N

* A
* B
* C
* D
* E
* F
* G
* H
* I
* J
* K
* L
* M
* N
* O
* P
* Q
* R
* S
* T
* U
* V
* W
* X
* Y
* Z
* †Namatomys
** †Namatomys erythrus – type locality for species
** †Namatomys lloydi
* †Nannodectes
** †Nannodectes gazini – type locality for species
** †Nannodectes gidleyi
** †Nannodectes intermedius – type locality for species
** †Nannodectes simpsoni – type locality for species
* †Nanodelphys
** †Nanodelphys hunti
* †Nanomomys
** †Nanomomys thermophilus
* †Nanotragulus
** †Nanotragulus loomisi – type locality for species
** †Nanotragulus ordinatus
* †Naocephalus – type locality for genus
** †Naocephalus porrectus – type locality for species
* †Navajovius
** †Navajovius kohlhaasae
* †Neanis
** †Neanis schucherti
* †Necrocydnus
** †Necrocydnus gosiutensis – type locality for species
* †Necygonus – type locality for genus
** †Necygonus rotundatus – type locality for species
* †Nelumbago
** †Nelumbago montanum
* A living Nelumbo lotus †Nelumbo
* †Neocathartes
** †Neocathartes grallator
* †Neodiacodexis
** †Neodiacodexis emryi
* †Neoliotomus
** †Neoliotomus conventus
** †Neoliotomus ultimus
* Mounted fossilized skeleton of the Miocene Neophrontops Neophrontops
** †Neophrontops americana
** †Neophrontops americanus
* †Neoplagiaulax
** †Neoplagiaulax grangeri – tentative report
** †Neoplagiaulax hunteri
** †Neoplagiaulax jepi – type locality for species
** †Neoplagiaulax mckennai – type locality for species
** †Neoplagiaulax nelsoni
* †Neothanes
** †Neothanes testeus – type locality for species
* Neotoma
* †Neovulpavus
** †Neovulpavus washakius
* †Nexuotapirus
** †Nexuotapirus marslandensis
* †Niglarodon
* †Niptomomys
** †Niptomomys doreenae
** †Niptomomys favorum – type locality for species
** †Niptomomys thelmae
* †Nonomys
** †Nonomys simplicidens
* †Nordenskioldia
** †Nordenskioldia borealis
* †Nosodendron
** †Nosodendron tritavum – type locality for species
* †Notharctus
** †Notharctus robinsoni – type locality for species
** †Notharctus robustior
** Mounted fossilized skeleton of the Eocene primate Notharctus tenebrosus †Notharctus tenebrosus – type locality for species
** †Notharctus venticolus
* †Notogoneus
* †Notomorpha – type locality for genus
** †Notomorpha garmanii – type locality for species
** †Notomorpha gravis – type locality for species
** †Notomorpha testudinea – type locality for species
* †Notoparamys – tentative report
** †Notoparamys blochi – type locality for species
* †Nototamias – or unidentified comparable form
* †Nucifraga
** †Nucifraga columbiana
* Numenius
** †Numenius americanus
** A taxidermied Numenius borealis, or Eskimo curlew †Numenius borealis
* †Nyctea
** †Nyctea scandiaca
* †Nyctitherium
** †Nyctitherium christopheri
** †Nyctitherium gunnelli – type locality for species
** †Nyctitherium serotinum – type locality for species
** †Nyctitherium velox
* †Nyssa
** †Nyssa alata
** †Nyssa borealis

## O

* A
* B
* C
* D
* E
* F
* G
* H
* I
* J
* K
* L
* M
* N
* O
* P
* Q
* R
* S
* T
* U
* V
* W
* X
* Y
* Z
* Ochotona
** A living Ochotona princeps, or American pika †Ochotona princeps
* Ocotea
** †Ocotea coloradensis
** †Ocotea FW03 informal
* †Odaxosaurus
** †Odaxosaurus jepseni – or unidentified comparable form
** †Odaxosaurus piger
* †Ogmophis
** †Ogmophis microcompactus – or unidentified comparable form
** †Ogmophis voorhiesi
* †Oligodontosaurus – type locality for genus
** †Oligodontosaurus wyomingensis – type locality for species
* †Oligoryctes
** †Oligoryctes altitalonidus
** †Oligoryctes cameronensis
* †Oligoscalops – tentative report
* †Oligospermophilus
* †Oligotheriomys
** †Oligotheriomys senrudi
* †Oliveremys
** †Oliveremys uintaensis – type locality for species
* †Omalodiscus
* †Omomys
** †Omomys carteri
** †Omomys lloydi
* Ondatra
** †Ondatra meadensis
* †Onoclea
** †Onoclea hesperia
* Restoration of the Eocene bat Onychonycteris †Onychonycteris – type locality for genus
** †Onychonycteris finneyi – type locality for species
* †Oodectes
** †Oodectes herpestoides – type locality for species
** †Oodectes jepseni
* Ophryastes
** †Ophryastes compactus – type locality for species
* †Opisthotriton
** †Opisthotriton kayi
* A living Oreamnos, or mountain goat Oreamnos
* †Oreoconus
* †Oreodontoides
** †Oreodontoides oregonensis
* Oreohelix
** †Oreohelix megarche
* †Oreolagus
** †Oreolagus colteri
** †Oreolagus nebrascensis
* †Oreopanax
** †Oreopanax elongatum
* †Ormiscus
** †Ormiscus partitus – type locality for species
* Mounted fossilized skeleton of the Eocene horse Orohippus †Orohippus
** †Orohippus major – type locality for species
** †Orohippus proteros
** †Orohippus pumilus – type locality for species
** †Orohippus sylvaticus
* †Orthogenysuchus – type locality for genus
** †Orthogenysuchus olseni – type locality for species
* †Osbornodon
** †Osbornodon brachypus – type locality for species
* †Osmanthus
** †Osmanthus praemissa
* Living Osmunda ferns †Osmunda
** †Osmunda affinis
* †Osmundacidites
* †Otarocyon
** †Otarocyon cooki
* †Otiorhynchites
** †Otiorhynchites fossilis – type locality for species
** †Otiorhynchites tysoni
* †Otiorhynchus
** †Otiorhynchus dubius – type locality for species
** †Otiorhynchus perditus – type locality for species
* †Ototriton – type locality for genus
** †Ototriton solidus – type locality for species
* †Ourayia
** †Ourayia hopsoni
** †Ourayia uintensis
* Ovis
** A living Ovis canadensis, or bighorn sheep †Ovis canadensis
* †Oxyacodon
** †Oxyacodon agapetillus
** †Oxyacodon apiculatus
** †Oxyacodon priscilla
* †Oxyaena
** †Oxyaena forcipata
** †Oxyaena gulo
** †Oxyaena intermedia
** †Oxyaena lupina
* †Oxyclaenus
** †Oxyclaenus cuspidatus
* Life restoration of a pair of the Oligocene-Miocene camel Oxydactylus. Robert Bruce Horsfall (1913). †Oxydactylus
** †Oxydactylus longipes – or unidentified comparable form
** †Oxydactylus lulli – type locality for species
** †Oxydactylus wyomingensis
* †Oxyprimus
** †Oxyprimus galadrielae – type locality for species
** †Oxyprimus putorius

## P

* A
* B
* C
* D
* E
* F
* G
* H
* I
* J
* K
* L
* M
* N
* O
* P
* Q
* R
* S
* T
* U
* V
* W
* X
* Y
* Z
* Fossilized mandibles of the Paleocene-Eocene mesonychian mammal Pachyaena †Pachyaena
** †Pachyaena gigantea
** †Pachyaena gracilis
** †Pachyaena ossifraga
* Pachycondyla
** †Pachycondyla labandeirai – type locality for species
* †Pachylobius
** †Pachylobius compressus
* †Palaeanodon
** †Palaeanodon ignavus
** †Palaeanodon Ignavus
** †Palaeanodon nievelti
** †Palaeanodon parvulus – tentative report
* †Palaearctonyx
** †Palaearctonyx meadi – type locality for species
* †Palaechthon
** †Palaechthon alticuspis – or unidentified comparable form
** †Palaechthon woodi
* †Palaeictops
** †Palaeictops bicuspis
** †Palaeictops bridgeri
** †Palaeictops multicuspis
* †Palaeocarpinus
** †Palaeocarpinus aspinosa
* †Palaeocarya
** †Palaeocarya clarnensis
* †Palaeogale
** †Palaeogale sanguinarius
** †Palaeogale sectoria
* Restoration of the Oligocene rabbit relative Palaeolagus †Palaeolagus
** †Palaeolagus burkei
** †Palaeolagus haydeni
** †Palaeolagus hypsodus – type locality for species
** †Palaeolagus intermedius
** †Palaeolagus philoi
** †Palaeolagus primus – type locality for species
** †Palaeolagus temnodon
* †Palaeonictis
** †Palaeonictis occidentalis
** †Palaeonictis peloria – type locality for species
** †Palaeonictis wingi – type locality for species
* †Palaeophasianus – type locality for genus
** †Palaeophasianus meleagroides – type locality for species
* †Palaeorallus – type locality for genus
** †Palaeorallus troxelli – type locality for species
* †Palaeoryctes
** †Palaeoryctes cruoris – type locality for species
** †Palaeoryctes puercensis
** †Palaeoryctes punctatus
* †Palaeosinomenium – or unidentified comparable form
** †Palaeosinomenium venablesii
* †Palaeosinopa
** †Palaeosinopa didelphoides
** †Palaeosinopa dorri – type locality for species
** †Palaeosinopa incerta – type locality for species
** †Palaeosinopa lacus – type locality for species
** †Palaeosinopa lutreola
** †Palaeosinopa veterrima
* Restorative model and fossilized skull of the Eocene brontothere mammal Palaeosyops †Palaeosyops
** †Palaeosyops fontinalis
** †Palaeosyops paludosus – type locality for species
** †Palaeosyops robustus – type locality for species
* †Palaeotheca
** †Palaeotheca terrestris – type locality for species
* †Palaeoxantusia – type locality for genus
** †Palaeoxantusia amara – type locality for species
** †Palaeoxantusia fera – type locality for species
* †Palatobaena – type locality for genus
** †Palatobaena bairdi – type locality for species
** †Palatobaena gaffneyi – type locality for species
* †Palecphora
** †Palecphora patefacta – type locality for species
* †Palenochtha
** †Palenochtha minor
** †Palenochtha weissae – type locality for species
* †Paleoamphiuma – type locality for genus
** †Paleoamphiuma tetradactylum – type locality for species
* †Paleomyrtinaea
** †Paleomyrtinaea FW66 informal
* †Paleonelumbo
** †Paleonelumbo macroloba
* †Paleonuphar
** †Paleonuphar hesperium
* †Paleotomus
** †Paleotomus carbonensis – type locality for species
** †Paleotomus milleri – type locality for species
** †Paleotomus radagasti
* †Palepidophyma – type locality for genus
** †Palepidophyma lilliputiana – type locality for species
** †Palepidophyma paradisa – type locality for species
* Paliurus
** †Paliurus colombi
* †Palmocarpon
** †Palmocarpon subcylindricum
* †Pandaniidites
** †Pandaniidites radicus
* Panthera
** A living Panthera leo, or lion †Panthera leo
* †Pantolambda
** †Pantolambda cavirictus
** †Pantolambda intermedius – or unidentified comparable form
* †Pantolestes
** †Pantolestes longieundus – type locality for species
** †Pantolestes natans – or unidentified comparable form
* †Paracathartes
** †Paracathartes howardae
* †Paracosoryx
** †Paracosoryx wilsoni
* †Paracynarctus
** †Paracynarctus kelloggi
* †Paradjidaumo
** †Paradjidaumo hypsodus
** †Paradjidaumo trilophus
* †Paraenhydrocyon
** †Paraenhydrocyon josephi
** †Paraenhydrocyon robustus
** †Paraenhydrocyon wallovianus
* †Paraepicrates
** †Paraepicrates brevispondylus – type locality for species
* †Paraglyptosaurus
** †Paraglyptosaurus princeps – type locality for species
* †Parahippus
** †Parahippus pawniensis
** †Parahippus pristinus – tentative report
** †Parahippus wyomingensis – type locality for species
* †Paralatindia
** †Paralatindia saussurei – type locality for species
* †Paramerychyus
** †Paramerychyus harrisonensis
** †Paramerychyus relictus
* †Paramys
** †Paramys adamus – type locality for species
** †Paramys compressidens
** †Paramys copei
** †Paramys delicatior
** †Paramys delicatus
** †Paramys excavatus
** †Paramys leptodus
** †Paramys pycnus
** †Paramys relictus
** †Paramys taurus
* †Parandrita
** †Parandrita vestita – type locality for species
* †Paranolis – type locality for genus
** †Paranolis delicatus – type locality for species
* †Paranymphaea
** †Paranymphaea crassifolia
* †Paranymphea
** †Paranymphea crassifolia
* †Parapliosaccomys
** †Parapliosaccomys transversus
* †Paraprionosaurus – type locality for genus
** †Paraprionosaurus wyomingensis – type locality for species
* †Parapternodus
** †Parapternodus antiquus – type locality for species
* †Pararyctes
** †Pararyctes pattersoni – type locality for species
* †Parasauromalus – type locality for genus
** †Parasauromalus olseni – type locality for species
* †Paraternstroemia
** †Paraternstroemia hyphovenosa
* †Paratomarctus
** †Paratomarctus temerarius
* Life restoration the Eocene-Oligocene camel Paratylopus (upper right) †Paratylopus
** †Paratylopus labiatus
** †Paratylopus primaevus
* †Parectypodus
** †Parectypodus clemensi
** †Parectypodus lunatus
** †Parectypodus sinclairi
** †Parectypodus sylviae
* †Pareumys
** †Pareumys grangeri
* †Parictis
** †Parictis dakotensis
** †Parictis gilpini
** †Parictis parvus
** †Parictis personi
* †Paromomys
** †Paromomys depressidens
** †Paromomys maturus
* †Parophisaurus
** †Parophisaurus pawneensis
* †Parvericius
** †Parvericius montanus
* †Parvileguminophyllum
** †Parvileguminophyllum coloradensis
* †Parvitragulus
** †Parvitragulus priscus
* Life restoration of the Eocene creodont mammal Patriofelis. Charles R. Knight (1896). †Patriofelis
** †Patriofelis ferox – type locality for species
** †Patriofelis ulta
* †Patriomanis
** †Patriomanis americanus
* †Pauromys
** †Pauromys schaubi – type locality for species
* †Peltosaurus
* †Pelycodus
* †Pelycomys
** †Pelycomys placidus
* †Penetrigonias
** †Penetrigonias dakotensis
* †Penosphyllum
** †Penosphyllum cordatum
* †Pentacemylus – tentative report
* †Pentacodon
* †Pentacosmodon
** †Pentacosmodon pronus – type locality for species
* †Peradectes
** †Peradectes californicus
** †Peradectes chesteri
** †Peradectes elegans – type locality for species
** †Peradectes protinnaminatus
** †Peradectes protinnominatus
* Fossilized mandible of the Eocene-Miocene mammal Peratherium †Peratherium
** †Peratherium comstocki
** †Peratherium edwardi
** †Peratherium marsupium
* †Perchoerus
** †Perchoerus minor
* †Periptychus
** †Periptychus carinidens
** †Periptychus coarctatus
* Perognathus
** †Perognathus furlongi
* A living Peromyscus, or deer mouse Peromyscus
* Persea
** †Persea brossiana
** †Persea coriacea – type locality for species
** †Persea pseudocarolinensis
* †Perseoxylon
** †Perseoxylon aromaticum
* †Persites
** †Persites argutus
* †Petauristodon
* †Phalaenoptilus
** †Phalaenoptilus nuttallii
* †Phareodus
** †Phareodus encaustus
** †Phareodus testis
* †Phenacocoelus
** †Phenacocoelus typus
* †Phenacodaptes
** †Phenacodaptes sabulosus – type locality for species
* †Phenacodontid
* Life restoration of the Paleocene-Eocene ungulate Phenacodus. Charles R. Knight (1898). †Phenacodus
** †Phenacodus bisonensis – type locality for species
** †Phenacodus grangeri
** †Phenacodus intermedius
** †Phenacodus magnus
** †Phenacodus matthewi
** †Phenacodus trilobatus
** †Phenacodus vortmani
* †Phenacolemur
** †Phenacolemur fortior – type locality for species
** †Phenacolemur mcgrewi – type locality for species
** †Phenacolemur praecox
** †Phenacolemur shifrae
** †Phenacolemur simonsi
* Phenacomys
** †Phenacomys longicaudus
* †Phenolia
** †Phenolia incapax – type locality for species
* Philhydrus
* †Philodendron – or unidentified related form
** †Philodendron RR61 informal
* †Philotrox
** †Philotrox condoni
* Illustration of a fossilized skull in multiple views of the Oligocene-Miocene bone-crushing dog Phlaocyon †Phlaocyon
** †Phlaocyon annectens
** †Phlaocyon leucosteus
** †Phlaocyon minor
** †Phlaocyon multicuspus
* †Phoebe
* Phragmites – tentative report
** †Phragmites latissima
* †Phyllites
** †Phyllites crassifolia
** †Phyllites demoresi
* A living Phyllobius weevil Phyllobius
** †Phyllobius avus
* Physa
* Phytocrene
** †Phytocrene sordida
* Pica
** †Pica pica
* †Piceoerpeton – type locality for genus
** †Piceoerpeton willwoodense – type locality for species
* †Picrodus
** †Picrodus calgariensis
** †Picrodus canpacius
** †Picrodus silberlingi
* †Picromomys
** †Picromomys petersonorum – type locality for species
* A living Pinus, or pine tree Pinus
** †Pinus balli
** †Pinus florissanti
** †Pinus GR542 informal
** †Pinus gracilistrobus
** †Pinus iddingsi
** †Pinus Lesquereux
** †Pinus macrolepis
** †Pinus premurrayana
** †Pinus wardii
* †Pipestoneomys
** †Pipestoneomys bisulcatus – or unidentified comparable form
* Pipilo
** A living Pipilo chlorurus, or green-tailed towhee †Pipilo chlorurus
* †Plagioctenodon
** †Plagioctenodon krausae
** †Plagioctenodon rosei
** †Plagioctenodon savagei
** †Plagioctenodon thewisseni – type locality for species
* †Plagioctenoides
** †Plagioctenoides microlestes
** †Plagioctenoides tombowni
* †Plagiomene
** †Plagiomene accola
** †Plagiomene multicuspis
* †Planatus
** †Planatus raynoldsi
* Illustration of a branch with nuts from a Planera, or water elm tree †Planera
** †Planera longifolia
* †Planetetherium
** †Planetetherium mirabile
* †Planetochelys
** †Planetochelys dithyros
* †Planorbina
** †Planorbina pseudoammonius
* †Plastomenoides
** †Plastomenoides lamberti
* †Plastomenus
** †Plastomenus molopinus
** †Plastomenus oedemius – type locality for species
** †Plastomenus tantillus – type locality for species
** †Plastomenus thomasi
** †Plastomenus visendus – type locality for species
* †Plataninium
** †Plataninium haydeni
* †Platanophyllum
** †Platanophyllum whitneyi
* Leaves and fruit of a living Platanus, or plane tree Platanus
** †Platanus brownii
** †Platanus GR552 informal
** †Platanus gracilis
** †Platanus guillelmae
** †Platanus montana
** †Platanus raynoldsi
** †Platanus raynoldsii
** †Platanus wyomingensis
* Platycarya
** †Platycarya americana
** †Platycarya BB09 informal
** †Platycarya castaneopis
** †Platycarya castaneopsis
* Platynus
** †Platynus caesus – type locality for species
** †Platynus senex – type locality for species
* Plecia
** †Plecia dejecta – type locality for species
** †Plecia pealei – type locality for species
* Life restoration of the Paleocene-Eocene primate Plesiadapis †Plesiadapis
** †Plesiadapis anceps – type locality for species
** †Plesiadapis churchilli
** †Plesiadapis cookei
** †Plesiadapis dubius
** †Plesiadapis fodinatus – type locality for species
** †Plesiadapis gingerichi
** †Plesiadapis praecursor
** †Plesiadapis rex
** †Plesiadapis simonsi – type locality for species
* †Plesiolestes
** †Plesiolestes problematicus – type locality for species
* †Pliophenacomys
** †Pliophenacomys meadensis
** †Pliophenacomys primaevus
* †Poabromylus
** †Poabromylus golzi
* †Poebrodon
* Life restoration of the Eocene-Oligocene camel Poebrotherium †Poebrotherium
** †Poebrotherium eximium
** †Poebrotherium wilsoni
* †Poliomyia – type locality for genus
** †Poliomyia recta – type locality for species
* †Pollyosbornia
** †Pollyosbornia altidens – or unidentified comparable form
* Polygyra
* †Pontifactor
** †Pontifactor bestiola – type locality for species
* Montage of photographs in spring (top left), summer (top right), autumn (bottom left), and winter (bottom right) of Populus, or poplar tree Populus
** †Populus balsamoides
** †Populus cinnamomoides
** †Populus daphnogenoides
** †Populus FW60 informal
** †Populus glandulifera
** †Populus meigsii
** †Populus nebraskana
** †Populus speciosa
** †Populus vivaria
** †Populus wilmattae
** †Populus wyomingiana
** †Populus xantholithensis
* Porzana
** †Porzana carolina
* †Potamogeton
* †Premnoides
** †Premnoides douglassi
* Life restoration of the Paleocene-Eocene waterfowl Presbyornis †Presbyornis
* †Primobucco
** †Primobucco kistneri
** †Primobucco mcgrewi
* †Princetonia
** †Princetonia yalensis
* †Priscacara
* †Priscachara
* †Pristichampsus
* †Probathyopsis
** †Probathyopsis harrisorum
** †Probathyopsis lysitensis
** †Probathyopsis praecursor
* †Problastomeryx
** †Problastomeryx primus – type locality for species
* †Procaimanoidea
** †Procaimanoidea kayi – type locality for species
* †Procamelus
** †Procamelus grandis
* †Procerberus
** †Procerberus formicarum – or unidentified comparable form
** †Procerberus grandis – or unidentified comparable form
* †Prochetodon
** †Prochetodon cavus – type locality for species
** †Prochetodon foxi
** †Prochetodon taxus – type locality for species
* †Procydnus – tentative report
** †Procydnus mamillanus – type locality for species
* †Procynodictis
** †Procynodictis vulpiceps
* †Prodiacodon
** †Prodiacodon concordiarcensis – type locality for species
** †Prodiacodon furor – or unidentified comparable form
** †Prodiacodon puercensis – or unidentified comparable form
** †Prodiacodon tauricinerei
* †Proharrymys
** †Proharrymys schlaikjeri
* †Prolimnocyon
** †Prolimnocyon antiguus
** †Prolimnocyon antiquus
** †Prolimnocyon atavus
** †Prolimnocyon eerius
** †Prolimnocyon haematus – type locality for species
* †Promartes
** †Promartes lepidus
** †Promartes olcotti
** †Promartes vantasselensis
* Restoration of the Miocene hippopotamus-like oreodont Promerycochoerus both onshore and in the water. Robert Bruce Horsfall (1913). †Promerycochoerus
** †Promerycochoerus carrikeri
** †Promerycochoerus superbus
* †Promioclaenus
** †Promioclaenus acolytus
** †Promioclaenus pipiringosi – type locality for species
* †Pronemobius
** †Pronemobius induratus – type locality for species
** †Pronemobius tertiarius – type locality for species
* †Pronothodectes
** †Pronothodectes jepi – type locality for species
* †Propalaeanodon – type locality for genus
** †Propalaeanodon schaffi – type locality for species
* †Proscalops
** †Proscalops miocaenus
** †Proscalops secundus – or unidentified comparable form
* †Prosciurus
** †Prosciurus vetustus
* †Protadjidaumo – tentative report
** †Protadjidaumo typus
* †Protagras – type locality for genus
** †Protagras lacustris – type locality for species
* †Protamphipteryx – type locality for genus
** †Protamphipteryx basalis – type locality for species
* †Prothryptacodon
** †Prothryptacodon furens
** †Prothryptacodon hilli – type locality for species
* †Protictis
** †Protictis agastor – type locality for species
** †Protictis aprophatos
** †Protictis haydenianus
** †Protictis microlestes
** †Protictis paralus
* †Protoboysia
** †Protoboysia complicata
* Life restoration of a female (left) and male of the Oligocene-Miocene even-toed ungulate Protoceras. Charles R. Knight (1896). †Protoceras
** †Protoceras neatodelpha – type locality for species
* †Protochelydra
** †Protochelydra zangerli – or unidentified comparable form
* †Protochriacus
** †Protochriacus simplex – or unidentified comparable form
* †Protohippus
** †Protohippus perditus – or unidentified comparable form
* †Protolabis
** †Protolabis heterodontus – or unidentified comparable form
* †Protomarctus
** †Protomarctus optatus
* †Protopsalis
* †Protoptychus
** †Protoptychus hatcheri
* †Protoreodon
** †Protoreodon parvus – or unidentified comparable form
** †Protoreodon petersoni – or unidentified comparable form
** †Protoreodon pumilus
* Protorohippus †Protorohippus
** †Protorohippus montanum
** †Protorohippus venticolum
* †Protoselene – tentative report
** †Protoselene novissimus – type locality for species
* †Protospermophilus
** †Protospermophilus kelloggi
* †Protostrix
** †Protostrix leptosteus
** †Protostrix saurodosis – type locality for species
* †Prototomus
** †Prototomus deimos – type locality for species
** †Prototomus martis – type locality for species
** †Prototomus phobos
** †Prototomus robustus
** †Prototomus secundarius
* †Protungulatum
** †Protungulatum donnae
** †Protungulatum gorgun
** †Protungulatum sloani
* Illustration of a fossilized skull of the Eocene camel Protylopus †Protylopus
** †Protylopus petersoni
* †Provaranosaurus – type locality for genus
** †Provaranosaurus acutus – type locality for species
** †Provaranosaurus fatuus – type locality for species
* †Proviverroides
** †Proviverroides piercei
* †Proxestops
** †Proxestops silberlingii – type locality for species
* Prunus
** †Prunus corrugis
** †Prunus stewarti
* Restoration of the Miocene cat Pseudaelurus †Pseudaelurus
** †Pseudaelurus intrepidus
* †Pseudhipparion
** †Pseudhipparion retrusum
* †Pseudoblastomeryx
** †Pseudoblastomeryx advena
* †Pseudocemophora
** †Pseudocemophora antiqua – or unidentified comparable form
* †Pseudocrypturus – type locality for genus
** †Pseudocrypturus cercanaxius – type locality for species
* †Pseudocylindrodon
** †Pseudocylindrodon medius
** †Pseudocylindrodon tobeyi
* †Pseudodesmatochoerus – type locality for genus
** †Pseudodesmatochoerus hoffmani – type locality for species
* †Pseudolabis
** †Pseudolabis dakotensis
* †Pseudopalaeocastor
** †Pseudopalaeocastor osmagnus
* Fossilized skeleton of the Eocene protoceratid mammal Pseudoprotoceras †Pseudoprotoceras
** †Pseudoprotoceras longinaris
** †Pseudoprotoceras minor – type locality for species
** †Pseudoprotoceras taylori
* †Pseudotetonius
** †Pseudotetonius ambiguus
* †Pseudotheridomys
** †Pseudotheridomys pagei – or unidentified comparable form
* †Pseudotomus
** †Pseudotomus hians – type locality for species
** †Pseudotomus horribilis – type locality for species
** †Pseudotomus robustus – type locality for species
* †Psilosemys – type locality for genus
** †Psilosemys wyomingensis – type locality for species
* †Psilota
** †Psilota tabidosa – type locality for species
* Life restoration of the Paleocene taeniodont mammal Psittacotherium multifragum †Psittacotherium
** †Psittacotherium multifragum
* Ptelea
** †Ptelea cassioides
* Pteris – or unidentified related form
** †Pteris silvicola
* Pterocarya
** †Pterocarya glabra
** †Pterocarya hispida
** †Pterocarya macginitii
* †Pteromogoplistes
** †Pteromogoplistes smithii – type locality for species
* †Pterospermites
** †Pterospermites haguei
* Illustration of a fossilized skull of the Paleocene multituberculate mammal Ptilodus †Ptilodus
** †Ptilodus fractus
** †Ptilodus gnomus
** †Ptilodus kummae
** †Ptilodus mediaevus
** †Ptilodus montanus – or unidentified comparable form
** †Ptilodus tsosiensis – or unidentified comparable form
** †Ptilodus wyomingensis – type locality for species
* †Pulverflumen
** †Pulverflumen magnificum – type locality for species
* Puma
** †Puma concolor
* Pupilla – or unidentified comparable form
* †Pyramidula
** †Pyramidula ralstonensis
* †Pyrocyon
** †Pyrocyon dioctetus

## Q

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* Y
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* †Quadratomus
** †Quadratomus grandis
** †Quadratomus grossus
** †Quadratomus sundelli
* †Quercinium
** †Quercinium knowltoni
** †Quercinium lamarense
* A living Quercus, or oak tree Quercus
** †Quercus consimilis – tentative report
** †Quercus culveri
** †Quercus cuneatus – type locality for species
** †Quercus drymeja
** †Quercus furcinervis
** †Quercus GR522 informal
** †Quercus GR575 informal
** †Quercus greenlandica
** †Quercus grosidentata
** †Quercus hesperia
** †Quercus magnifolia
** †Quercus olafseni
** †Quercus petros – type locality for species
** †Quercus sullyi
** †Quercus weedii
** †Quercus yanceyi
* †Quereuxia
** †Quereuxia angulata
* A living Quiscalus, or grackle Quiscalus – or unidentified comparable form

## R

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* Life restoration of the Miocene-Pliocene pronghorn Ramoceros and Cosoryx. Robert Bruce Horsfall (1913). †Ramoceros
* †Rapamys
** †Rapamys wilsoni
* †Raphictis
** †Raphictis gausion – type locality for species
* †Reithroparamyine
* †Reithroparamys
** †Reithroparamys delicatissimus – type locality for species
** †Reithroparamys huerfanensis
* †Restes – type locality for genus
** †Restes rugosus – type locality for species
* †Reticuloidosporites
** †Reticuloidosporites pseudomurii
* †Rhamnacinium
** †Rhamnacinium radiatum
* †Rhamnus
** †Rhamnus cleburni
** †Rhamnus hirsuta
** †Rhamnus rectinervis
* Rhineura – type locality for genus
** †Rhineura hatcherii – type locality for species
* Rhinoclemmys – report made of unidentified related form or using admittedly obsolete nomenclature
** †Rhinoclemmys terrestris
* Rhus
** †Rhus mixta – tentative report
** A Rhus nigricans leaf †Rhus nigricans
* †Rhyssa
** †Rhyssa juvenis – type locality for species
* Flowers of a living Robinia †Robinia
** †Robinia wardi
* Rosa
** †Rosa hilliae
* †Rymosia
** †Rymosia strangulata – type locality for species

## S

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* Living Sabal, or palmettos Sabal
** †Sabal grayana
** †Sabal powelli
* †Sabalitesamesoneuron
** †Sabalitesamesoneuron RR34 informal
* †Saccoloma
** †Saccoloma gardneri
* †Sackenia
** †Sackenia gibbosa – type locality for species
* †Salilx
** †Salilx longiacuminata
* A living Salix, or willow Salix
** †Salix angusta
** †Salix aquilina
** †Salix cockerelli
** †Salix elongata – tentative report
** †Salix lavateri
** †Salix varians
* †Salpinctes – or unidentified comparable form
** †Salpinctes obsoletus
* †Salvinia
** †Salvinia preauriculata
* †Sanctimus
** †Sanctimus simonisi – type locality for species
** †Sanctimus stouti – type locality for species
** †Sanctimus stuartae
* Fossilized skeleton of the Eocene monitor lizard Saniwa †Saniwa – type locality for genus
** †Saniwa ensidens – type locality for species
** †Saniwa major – type locality for species
** †Saniwa stenodon
* †Sapindaceous
* †Sapindus
** †Sapindus alatus
** †Sapindus grandifolioloides
** †Sapindus grandifoliolus
** †Sapindus wardii
* Sassafras
** †Sassafras thermale
* †Scalopoides
* †Scapherpeton
** †Scapherpeton tectum
* †Scenopagus
** †Scenopagus curtidens
** †Scenopagus edenensis
** †Scenopagus hewettensis – type locality for species
** †Scenopagus priscus
* †Schaubeumys
** †Schaubeumys sabrae
* †Schizodontomys
** †Schizodontomys harkseni
** †Schizodontomys sulcidens
* Foliage of a living Schoepfia †Schoepfia
** †Schoepfia republicensis
* Sciara
** †Sciara scopuli – type locality for species
* †Scincoideus
** †Scincoideus grassator – type locality for species
* Sciomyza – tentative report
** †Sciomyza disjecta – type locality for species
** †Sciomyza manca – type locality for species
* †Sciophila
** †Sciophila hyatti – type locality for species
* †Sciuravus
** †Sciuravus bridgeri – type locality for species
** †Sciuravus nitidus – type locality for species
** †Sciuravus popi – or unidentified comparable form
** †Sciuravus wilsoni
* †Scottimus
** †Scottimus ambiguus – or unidentified comparable form
** †Scottimus kellamorum – type locality for species
** †Scottimus viduus
* †Selenaletes
** †Selenaletes scopaeus
* Sequoia
** †Sequoia couttsiae
** †Sequoia langsdorfii
** †Sequoia magnifica
* Life restoration of two species of the Oligocene oreodont mammal genus Sespia †Sespia
** †Sespia nitida
* †Shoshonius
** †Shoshonius bowni
** †Shoshonius cooperi
* †Sialia
* †Sifrhippus
** †Sifrhippus grangeri
** †Sifrhippus sandrae
* †Sigynorum – type locality for genus
** †Sigynorum magnadivisus – type locality for species
* †Simoedosaurus
* †Simpsonictis
** †Simpsonictis jaynanneae – type locality for species
** †Simpsonictis pegus – type locality for species
** †Simpsonictis tenuis
* †Simpsonlemur
** †Simpsonlemur citatus
** †Simpsonlemur jepseni – or unidentified comparable form
* †Sinclairella
* †Sinomenium – or unidentified related form
** †Sinomenium RR08 informal
* Fossilized skeleton of the Eocene-Oligocene creodont mammal Sinopa †Sinopa
** †Sinopa agilis – type locality for species
** †Sinopa major – type locality for species
** †Sinopa minor
** †Sinopa rapax – type locality for species
** †Sinopa viverrinus
* †Siphonophoroides
** †Siphonophoroides antiqua – tentative report
* Siren
** †Siren dunni – type locality for species
* Sitona
** †Sitona grandaevus – type locality for species
** †Sitona paginarum
* Sloanea – or unidentified related form
** †Sloanea RR18 informal
* †Smilax
** †Smilax GR550 informal
** †Smilax lamarensis
* Mounted fossilized skeleton of the Eocene primate Smilodectes †Smilodectes
** †Smilodectes gibossus – type locality for species
** †Smilodectes gracilis – type locality for species
** †Smilodectes mcgrewi – type locality for species
** †Smilodectes sororis – type locality for species
* Sorex
** †Sorex hoyi
* †Sparganium
** †Sparganium stygium
* †Spathorhynchus – type locality for genus
** †Spathorhynchus fossorium – type locality for species
** †Spathorhynchus natronicus
* Spermophilus
** †Spermophilus primitivus
** †Spermophilus variegatus
* †Sphacorhysis
** †Sphacorhysis burntforkensis – type locality for species
* Life restoration of the Eocene brontothere mammal Sphenocoelus †Sphenocoelus
** †Sphenocoelus hyognathus
** †Sphenocoelus uintensis
* Spirodela
** †Spirodela magna
* †Spiza
** †Spiza americana
* †Spurimus
** †Spurimus scotti
** †Spurimus selbyi
* Stagnicola
* †Staphylinites
** †Staphylinites obsoletum – type locality for species
* †Stegobium
** †Stegobium defunctus – type locality for species
* †Steinius
** †Steinius annectens – type locality for species
** †Steinius vespertinus
* †Steneofiber
** †Steneofiber fossor
** †Steneofiber gradatus
* †Stenocinclis – type locality for genus
** †Stenocinclis anomala – type locality for species
* †Stenogomphus
** †Stenogomphus scudderi – type locality for species
* Life restoration of the Oligocene-Miocene camel Stenomylus †Stenomylus
** †Stenomylus gracilis
** †Stenomylus hitchcocki
** †Stenomylus keelinensis
* †Stenopelta
** †Stenopelta punctulata – type locality for species
* Sterculia
** †Sterculia coloradensis
* †Stibarus
** †Stibarus quadricuspis
** †Stibarus yoderensis
* †Stillingia
** †Stillingia casca
* †Straitopollis
** †Straitopollis tectatus
* †Strigorhysis – type locality for genus
** †Strigorhysis bridgerensis – type locality for species
** †Strigorhysis rugosus
* Sturnella
** †Sturnella neglecta
* †Stygimys
** †Stygimys gratus
** †Stygimys kuszmauli
* Mounted fossilized skeleton of the Eocene-Oligocene tortoise Stylemys †Stylemys
** †Stylemys nebrascensis
* †Stylinodon
** †Stylinodon mirus – type locality for species
* †Styrax
** †Styrax transversa
* †Subhyracodon
** †Subhyracodon mitis
** †Subhyracodon occidentalis
* Surnia
** †Surnia ulula
* †Suzanniwana – type locality for genus
** †Suzanniwana patriciana – type locality for species
** †Suzanniwana revenanta – type locality for species
* †Swaindelphys
** †Swaindelphys cifellii – type locality for species
* †Swainiguanoides – type locality for genus
** †Swainiguanoides milleri – type locality for species
* †Swartzia
** †Swartzia wardelii – type locality for species
* Sylvicola – type locality for genus
** †Sylvicola cadaver – type locality for species
* Sylvilagus
* Symplocos
** †Symplocos exilis
* Synaptomys
* †Syncolporites
** †Syncolporites minimus
* Life restoration of the Miocene protoceratid mammal Syndyoceras †Syndyoceras
** †Syndyoceras cooki
* †Syntomostylus
** †Syntomostylus fortis – type locality for species
* Syrphus
* †Systemodon
** †Systemodon tapirinus
* †Syzygioides
** †Syzygioides americana

## T

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* Tachycineta – or unidentified comparable form
** †Tachycineta bicolor
* Restoration of the Paleocene multituberculate mammal Taeniolabis †Taeniolabis
** †Taeniolabis taoensis
* †Talpavoides
** †Talpavoides dartoni – type locality for species
* †Talpavus
** †Talpavus duplus
** †Talpavus nitidus
** †Talpavus sullivani – type locality for species
* Tamias
** †Tamias ateles – or unidentified comparable form
* †Tanymykter
** †Tanymykter brachyodontus
* Life restoration of the Eocene carnivoran relative Tapocyon †Tapocyon
** †Tapocyon robustus – or unidentified comparable form
* †Tarka
** †Tarka stylifera
* †Tatmanius – type locality for genus
** †Tatmanius szalayi – type locality for species
* Taxidea
** †Taxidea taxus
* †Taxites
** †Taxites olriki
* Taxodium
** †Taxodium olriki
** †Taxodium olrikii
* †Taxonus
** †Taxonus nortoni – type locality for species
* †Taxymys
** †Taxymys lucaris
* Fossilized mandible of the Eocene primate Teilhardina †Teilhardina
** †Teilhardina americana – type locality for species. Late reclassified in the new genus Bownomomys as the species B. americanus.
** †Teilhardina brandti – type locality for species
** †Teilhardina crassidens – type locality for species. Later reclassified as Bownomomys crassidens.
** †Teilhardina demissa – type locality for species
** †Teilhardina gingerichi
** †Teilhardina mathewi
** †Teilhardina tenuicula
* †Teleoceras
* †Telmatherium
** †Telmatherium validum – or unidentified comparable form
** †Telmatherium validus – type locality for species
* †Telmatrechus
** †Telmatrechus parallelus – type locality for species
* †Temnocyon
** †Temnocyon macrogenys – type locality for species
* †Temnotrionyx – type locality for genus
** †Temnotrionyx manducans – type locality for species
* †Teretrum
** †Teretrum quiescitum – type locality for species
* †Ternstroemites
** †Ternstroemites aureavallis
* †Tetigonia
** †Tetigonia priscomarginata – type locality for species
** †Tetigonia priscovariegata – type locality for species
* †Tetonius
** †Tetonius matthewi – type locality for species
* †Tetonoides
** †Tetonoides pearcei
* †Tetraclaenodon
** †Tetraclaenodon puercensis
* †Tetrapassalus
** †Tetrapassalus proius – type locality for species
* †Thamnotettix
** †Thamnotettix gannetti – type locality for species
** †Thamnotettix mutilata – type locality for species
* A modern uprooted Thelypteris, or maiden fern Thelypteris
** †Thelypteris iddingsi
** †Thelypteris iddingsii
* †Thinocyon
* †Thisbemys
** †Thisbemys brevicrista
** †Thisbemys corrugatus – type locality for species
** †Thisbemys perditus
* †Thouinia
** †Thouinia eocenica
* †Thryptacodon
** †Thryptacodon antiquus
** †Thryptacodon australis
** †Thryptacodon barae
** †Thryptacodon orthogonius – type locality for species
** †Thryptacodon pseudarctos
* †Thuites
** †Thuites interruptus
* †Thuja
** †Thuja interrupta
** †Thuja interruptus
* †Thylacaelurus
** †Thylacaelurus montanus – or unidentified comparable form
* †Thylacodon
** †Thylacodon pusillus
* A living member of Tilia, the genus including the lindens and basswoods Tilia
** †Tilia populifolia
* †Tillodon
** †Tillodon fodiens – type locality for species
* †Tillomys
** †Tillomys parvidens – type locality for species
** †Tillomys senex
* †Tinimomys
** †Tinimomys graybulliensis
** †Tinimomys loomisi
** †Tinimomys tribos – type locality for species
* Tinosaurus – type locality for genus
** †Tinosaurus pristinus – type locality for species
** †Tinosaurus stenodon – type locality for species
* Tipula
** †Tipula sepulchri – type locality for species
** †Tipula spoliata – type locality for species
* Life restoration of the Paleocene pantodont mammal Titanoides †Titanoides
** †Titanoides gidleyi – type locality for species
** †Titanoides major
** †Titanoides nanus – type locality for species
** †Titanoides primaevus
* †Titanomyrma
** Titanomyrma lubei with a rufous hummingbird for scale †Titanomyrma lubei – type locality for species
* †Torrejonia
** †Torrejonia sirokyi – type locality for species
* †Toxotherium
** †Toxotherium hunteri
* Trapa
** †Trapa angulata
** †Trapa paulula
* †Tremanotus
** †Tremanotus angustata
* †Triatriopollenites
** †Triatriopollenites granulatus
** †Triatriopollenites granulus
* †Tricalpites
** †Tricalpites parvus
* †Tricentes
** †Tricentes subtrigonus
* †Tricolpites
** †Tricolpites anguloluminosus + bathyreticulatus
** †Tricolpites anguloluminosus + bothyreticulatus
** †Tricolpites angulolumonosus + bathyreticulatus
** †Tricolpites mutabilis
** †Tricolpites parvus
* †Trigenicus
** †Trigenicus profectus
* †Trigonias
** †Trigonias osborni
* †Trigonorhinus
** †Trigonorhinus pristinus – type locality for species
* Trionyx
** †Trionyx concentricus – type locality for species
** †Trionyx thomasii – type locality for species
* †Triplopus
** †Triplopus cubitalis – type locality for species
** †Triplopus implicatus – type locality for species
** †Triplopus obliquidens – or unidentified comparable form
* Life restoration of the Eocene creodont mammal Tritemnodon †Tritemnodon
** †Tritemnodon strenuus
* †Tritoma
** †Tritoma binotata – type locality for species
* †Triumfetta
** †Triumfetta ovata
* †Trochodendroides
** †Trochodendroides flabella
* †Trogolemur
** †Trogolemur amplior – type locality for species
** †Trogolemur fragilis – type locality for species
** †Trogolemur myodes – type locality for species
* †Trogosus
** †Trogosus castoridens – type locality for species
** †Trogosus gazini – type locality for species
** †Trogosus latidens
* †Tropideres
** †Tropideres remotus – type locality for species
* †Tropisternus
** †Tropisternus saxialis – type locality for species
** †Tropisternus sculptilis – type locality for species
* †Trypodendron
** †Trypodendron impressus – type locality for species
* †Tsoabichi – type locality for genus
** †Tsoabichi greenriverensis – type locality for species
* †Tubulodon
** †Tubulodon atopum
** †Tubulodon pearcei
** †Tubulodon taylori
** †Tubulodon woodi
* Turdus – or unidentified comparable form
** †Turdus migratorius
* †Tuscahomys
** †Tuscahomys ctenodactylops – type locality for species
** †Tuscahomys major – or unidentified comparable form
** †Tuscahomys walshi – type locality for species
** †Tuscahomys worlandensis
* †Tylocephalonyx
** †Tylocephalonyx skinneri
* Tympanuchus
** A living Tympanuchus phasianellus, or sharp-tailed grouse †Tympanuchus phasianellus
* Typha – or unidentified related form
* †Tytthaena
** †Tytthaena lichna
** †Tytthaena parrisi – type locality for species

## U

* A
* B
* C
* D
* E
* F
* G
* H
* I
* J
* K
* L
* M
* N
* O
* P
* Q
* R
* S
* T
* U
* V
* W
* X
* Y
* Z
* †Uintaceras
** †Uintaceras radinskyi
* †Uintacyon
** †Uintacyon asodes
** †Uintacyon gingerichi
** †Uintacyon jugulans – type locality for species
** †Uintacyon massetericus
** †Uintacyon rudis
* †Uintanius
** †Uintanius ameghini
** †Uintanius rutherfurdi
* †Uintasorex
** †Uintasorex parvulus – type locality for species
* Life restoration of the Eocene mammal Uintatherium †Uintatherium – type locality for genus
** †Uintatherium anceps – type locality for species
* †Uintornis – type locality for genus
** †Uintornis lucaris – type locality for species
** †Uintornis marionae – type locality for species
* Ulmus
** †Ulmus microphylla
** †Ulmus minima – tentative report
** †Ulmus rhamnifolia
* Unio
* †Unuchinia
** †Unuchinia diaphanes – type locality for species
** †Unuchinia dysmathes
* Ursus
** A living Ursus arctos, or brown bear †Ursus arctos
* †Ustatochoerus
** †Ustatochoerus medius
* †Utahia
** †Utahia carina – type locality for species
* †Utemylus
** †Utemylus serior – type locality for species

## V

* A
* B
* C
* D
* E
* F
* G
* H
* I
* J
* K
* L
* M
* N
* O
* P
* Q
* R
* S
* T
* U
* V
* W
* X
* Y
* Z
* †Valenia
** †Valenia wilsoni
* †Valenopsalis
** †Valenopsalis joyneri
* †Vassacyon
** †Vassacyon bowni – type locality for species
** †Vassacyon promicrodon
* †Vauquelinia
** †Vauquelinia comptonifolia
* †Viburnum
** †Viburnum antiquorum
** †Viburnum antiquum
** †Viburnum asperum
* †Vinea – or unidentified comparable form
** †Vinea pugetensis
* Leaves and fruit of a living Vitis, or grapevine Vitis
** †Vitis olriki
** †"Vitis" stantoni
* †Viverravus
** †Viverravus acutus
** †Viverravus acutus/gracilis informal
** †Viverravus browni
** †Viverravus gracilis – type locality for species
** †Viverravus laytoni
** †Viverravus lutosus
** †Viverravus minutus – type locality for species
** †Viverravus politus
** †Viverravus rosei – type locality for species
** †Viverravus sicarius
* Viviparus
* Mounted fossilized skeleton of the Eocene mammal Vulpavus †Vulpavus
** †Vulpavus australis
** †Vulpavus canavus
** †Vulpavus farsonensis – type locality for species
** †Vulpavus hargeri
** †Vulpavus ovatus – type locality for species
** †Vulpavus palustris – type locality for species
** †Vulpavus profectus – type locality for species
** †Vulpavus simplex
* Vulpes
** A living Vulpes vulpes, or red fox †Vulpes vulpes

## W

* A
* B
* C
* D
* E
* F
* G
* H
* I
* J
* K
* L
* M
* N
* O
* P
* Q
* R
* S
* T
* U
* V
* W
* X
* Y
* Z
* †Washakius
** †Washakius insignis
** †Washakius izetti
* †Wickia
** †Wickia brevirhinus – or unidentified comparable form
* †Wilsoneumys
** †Wilsoneumys planidens
* Living Woodwardia ferns †Woodwardia
** †Woodwardia arctica
** †Woodwardia gravida
** †Woodwardia preareolata
* †Worlandia
** †Worlandia inusitata – type locality for species
* †Wrightohyus
** †Wrightohyus yatkolai
* †Wyolestes
** †Wyolestes apheles
** †Wyolestes dioctes – type locality for species
* †Wyomomys
** †Wyomomys bridgeri – type locality for species
* †Wyomylus – type locality for genus
** †Wyomylus whitei – type locality for species
* †Wyonycteris – type locality for genus
** †Wyonycteris chalix – type locality for species

## X

* A
* B
* C
* D
* E
* F
* G
* H
* I
* J
* K
* L
* M
* N
* O
* P
* Q
* R
* S
* T
* U
* V
* W
* X
* Y
* Z
* †Xanclomys
** †Xanclomys mcgrewi – type locality for species
* †Xenicohippus
** †Xenicohippus craspedotum
** †Xenicohippus grangeri
* †Xenochelys
** †Xenochelys bridgerensis – type locality for species
** †Xenochelys formosa
** †Xenochelys lostcabinensis – type locality for species
* †Xenocranium
* †Xestops
** †Xestops gracilis – type locality for species
** †Xestops lentus – type locality for species
** †Xestops microdus – type locality for species
** †Xestops minutus – type locality for species
** †Xestops piercei – type locality for species
** †Xestops savagei – type locality for species
** †Xestops vagans – type locality for species
** †Xestops vagrans
* †Xyronomys
** †Xyronomys swainae – type locality for species

## Y

* A
* B
* C
* D
* E
* F
* G
* H
* I
* J
* K
* L
* M
* N
* O
* P
* Q
* R
* S
* T
* U
* V
* W
* X
* Y
* Z
* †Yoderimys – type locality for genus
** †Yoderimys bumpi – type locality for species
** †Yoderimys stewarti
* Life restoration of the Miocene bear dog Ysengrinia †Ysengrinia
** †Ysengrinia americana

## Z

* A
* B
* C
* D
* E
* F
* G
* H
* I
* J
* K
* L
* M
* N
* O
* P
* Q
* R
* S
* T
* U
* V
* W
* X
* Y
* Z
* †Zamia
** †Zamia coloradensis
** †Zamia colorodensis
** †Zamia wyomingensis
* †Zangerlichelys
** †Zangerlichelys aequa
* †Zanycteris
** †Zanycteris paleocenus
* Zelkova
** †Zelkova nervosa
* †Zemiodontomys
** †Zemiodontomys burkei
* Zenaida
** †Zenaida rnacroura
* †Ziamys – or unidentified comparable form
* †Zingiberopsis
** †Zingiberopsis isonervosa
* Zizyphus
** †Zizyphus serrulatus
* †Zodiolestes
* Zonotrichia
** A living Zonotrichia albicollis, or white-throated sparrow †Zonotrichia albicollis