# Como Bluff

Como Bluff is a long ridge extending east–west, located between the towns of Rock River and Medicine Bow, Wyoming. The ridge is an anticline, formed as a result of compressional geological folding. Three geological formations, the Sundance, the Morrison, and the Cloverly Formations, containing fossil remains from the Late Jurassic of the Mesozoic Era, are exposed.
Nineteenth-century paleontologists discovered many well-preserved specimens of dinosaurs, as well as mammals, turtles, crocodilians, and fish from the Morrison Formation. Because of this, Como Bluff is considered to be one of the major sites for the early discovery of dinosaur remains. Among the species discovered is the only known specimen of Coelurus. Significant discoveries were made in 22 different areas scattered along the entire length of the ridge. It is included on the National Register of Historic Places as well as the National Natural Landmark list.

## History of discovery

The discovery of dinosaurs at Como Bluff has been recounted numerous times, most notably by Schuchert and LeVene, Shur, Ostrom and McIntosh, and Jaffe. Most of the specimens were collected by men working for O.C. Marsh between 1877 and 1889, although some were collected by the Hubbel brothers for E.D. Cope between 1879 and 1880. The American Museum of Natural History (AMNH) excavated in 1897 -1898 , finding two partial skeletons of sauropods. A summary of the quarries and their contents is given below.
In later years, the American Museum of Natural History and Yale University jointly reopened Quarry 9, the Mammal Quarry, 1968–1970, finding only a few specimens. More recently, Robert Bakker has done some collecting there with a variety of groups.
In addition to the major significance of dinosaur discoveries at Como Bluff, the site has also been the source of significant early mammal fossils. In early 1878, Marsh was ecstatic to find that one of his men had uncovered a fossil from a Jurassic mammal. Within a year, the historic Quarry 9 at Como was discovered, producing an astounding 250 specimens, which increased the knowledge of Jurassic mammals exponentially.

## Como Bluff historical quarries (pre-1900)

Data source:.
. . (h)= holotype

### AMNH Quarries

Excavated by the American Museum of Natural History

#### AMNH Quarry 1
##### Dinosauria

    Saurischia
       Sauropoda
          Diplodocus sp

#### AMNH Quarry 2
##### Dinosauria

    Saurischia
       Sauropoda
          Brontosaurus excelsus
          Camarasaurus sp,

#### AMNH localities unknown

(some could be from Quarry 1 or 2)

##### Reptilia

    Testudines
       Amphichelydia
          Glyptops plicatus
    Squamata
       ?Sauria indeterminant
       Lacertilia
          Paramacellodus sp.
    Choristodera
          Cteniogenys antiquus
    Crocodilia
       Mesosuchia
          Goniopholis sp.

### Frederick Brown's Quarries
#### Brown's Quarry A
##### Dinosauria

    Ornithischia
       Stegosauria
          Stegosaurus sp.

#### Brown's Quarry B
##### Dinosauria

    Ornithischia
       Stegosauria
          Stegosaurus sp.

#### Brown's Quarry C
##### Dinosauria

    Saurischia
       Theropoda
          Allosaurus fragilis

#### Brown's Quarry D
##### Dinosauria

    Saurischia
       Theropoda
          Allosaurus fragilis

#### Brown's Quarry G
##### Dinosauria

    Saurischia
       Sauropoda
          Camarasaurus sp.

### Arthur Lakes Quarry 1A. (Big Canyon Quarry)

Excavated by Arthur Lakes.

#### Dinosauria

    Saurischia
       Theropoda
          Allosaurus sp.
       Sauropoda
          Camarasaurus sp.
    Ornithischia
       Ornithopoda
          Camptosaurus amplus (h) (now Allosaurus sp.)

### E.D. Cope's Quarries

Excavated by Edward Drinker Cope

#### Cope's Quarry 3
##### Dinosauria

    Saurischia
       Theropoda
          Allosaurus sp.

#### Cope's Quarry 4
##### Dinosauria

    Saurischia
       Theropoda
          Allosaurus sp.
    Ornithischia
       Stegosauria
          Stegosaurus sp.

#### Cope's Quarry 5
##### Reptilia

    Pterosauria
          Dermodactylus montanus

##### Dinosauria

    Saurischia
       Sauropoda
          Apatosaurus sp.

#### Cope's localities unknown

(could be from Quarry 1, 2)

##### Reptilia

    Testudines
       Amphichelydia
          Dinochelys sp.
          Glyptops plicatus
    Crocodilia
       Mesosuchia
          Goniopholis sp.

##### Dinosauria

    Ornithischia
       Ornithopoda
          ?Camptosaurus sp.
       Stegosauria
          Stegosaurus sp.

##### Mammalia

    genus and species indeterminant

### William Harlow Reed's Quarries

Excavated by William Harlow Reed.

#### Reed's Quarry 1
##### Dinosauria

    Saurischia
       Theropoda
          Allosaurus atrox (h) (now Allosaurus fragilis)
       Sauropoda
          Camarasaurus grandis (h)
          Camarasaurus impar (h) (now Camarasaurus grandis)
          Camarasaurus robustus (h) (now Camarasaurus grandis)
          Pleurocoelus montanus (h) (now Camarasaurus grandis)
          Diplodocus sp.

##### Mammalia

          genus and species indeterminant

#### Reed's Quarry 1 ½
##### Dinosauria

    Saurischia
       Theropoda
          Allosaurus fragilis
       Sauropoda
          genus and species indeterminant

#### Reed's Quarry 2
##### Dinosauria

    Saurischia
       Sauropoda
          Apatosaurus sp.

#### Reed's Quarry 3
##### Dinosauria

    Saurischia
       Theropoda
          Allosaurus lucaris (h) (now Allosaurus sp.)
       Sauropoda
          Camarasaurus grandis
    Ornithischia
       Ornithopoda
          Dryosaurus sp.
       Stegosauria
          Stegosaurus sp.

#### Reed's Quarry 4
##### Dinosauria

    Saurischia
       Theropoda
          Allosaurus fragilis
       Sauropoda
          Apatosaurus sp.
          Barosaurus sp.
          Camarasaurus sp.
    Ornithischia
       Stegosauria
          Stegosaurus sp.

#### Reed's Quarry 5
##### Reptilia

    Pterosauria
          Dermodactylus montanus (h) (now nomen dubium)

##### Dinosauria

    Saurischia
       Sauropoda
          Diplodocus sp.
    Ornithischia
       Ornithopoda
          Dryosaurus altus (h)

#### Reed's Quarry 6
##### Reptilia

    Crocodylia
       Mesosuchia
          Goniopholis sp.

#### Reed's Quarry 7 (Three Trees Quarry)
##### Dinosauria

    Ornithischia
       Ornithopoda
          Laosaurus consors (h) (now Othnielosaurus consors)

#### Reed's Quarry 8
##### Reptilia

    Testudines
       genus and species indeterminant
    Crocodilia
       Mesosuchia
          Goniopholis sp.

##### Dinosauria

    Saurischia
       Theropoda
          Allosaurus sp.
          Coelurus fragilis
       Sauropoda
          Camarasaurus sp.
          Diplodocus sp.
    Ornithischia
       Stegosauria
          Stegosaurus sp.

#### Reed's Quarry 9 (Mammal Quarry)
##### Osteichthyes

    Actinopterygii
       genus and species indeterminant
    Amiiformes
       Ophiopsis sp.
    Sarcopterygii
       Dipnoi
          Ceratodus guentheri

##### Amphibia

    Anura
          Comobatrachus aenigmatis
       Discoglossoidea
          Enneabatrachus hechti
       Pelobatidae indeterminant
       Pipoidea?
          Eobatrachus agilis (h)
    Caudata
       genus and species indeterminant
       Comonecturoides marshi (h)

##### Reptilia

    Testudines
       Amphichelydia
          Dinochelys whitei
          Glyptops ornatus
    Squamata
       ?Sauria indeterminant
       Lacertilia
          Dorsetisaurus sp.
          Paramacellodus sp.
    Rhynchocephalia
          Opisthias rarus (h)
          Theretairus antiquus (h)
    Choristodera
          Cteniogenys antiquus (h)
    Crocodylia
       Sphenosuchia
          Macelognathus vagans (h)
       Mesosuchia
          Goniopholis sp.

##### Dinosauria

    Saurischia
       Theropoda
          Allosaurus fragilis
          Ceratosaurus nasicornis
          Coelurus fragilis
          Ornitholestes hermanni?
       Tyrannosauroidea
          Stokesosaurus clevelandi?
       Sauropoda
          Macronaria indeterminant
          Diplodocidae indeterminant
    Ornithischia
       Ornithopoda
          Othnielosaurus consors
          Dryosaurus sp.
          Camptosaurus sp.
    Stegosauria
          Stegosaurus sp.
    Pterosauria
       Rhamphorhynchoidea
          Laopteryx priscus (h) (now nomen dubium)

##### Mammalia

    Docodonta
       Docodontidae
          Docodon affinis (h)
          Docodon crassus (h)
          Docodon striatus (h)
          Docodon superus (h)
          Docodon victor (h)
    Multituberculata
       Allodontidae
          Ctenacodon laticeps (h)
          Ctenacodon scindens (h)
          Ctenacodon serratus (h)
          Psalodon fortis (h)
          Psalodon potens (h)
          ?Psalodon marshi (h)
    Triconodonta
       Amphilestidae
          Aploconodon comoensis (h)
          Comodon gidleyi (h)
       Triconodontidae
          Priacodon ferox (h)
          Priacodon grandaevus (h)
          Priacodon lulli (h)
          Priacodon robustus (h)
          Trioracodon bisulcus (h)
    Symmetrodonta
       Amphidontidae
          Amphidon superstes (h)
       Tinodontidae
          Tinodon bellus (h)
          Eurylambda aequicrurius
    Dryolestida
       Dryolestidae
          Amblotherium gracilis (h)
          Dryolestes priscus
          Dryolestes obtusus (h)
          Dryolestes vorax (h)
          Laolestes eminens (h)
          Laolestes (Melanodon) goodrichi (h)
          Laolestes (Melanodon) oweni (h)
          Miccylotyrans minimus (h)
       Paurodontidae
          Araeodon intermissus (h)
          Archaeotrigon brevimaxillus (h)
          Archaeotrigon distagmus (h)
          Comotherium richi (h)
          Euthlastus cordiformis (h)
          Paurodon valens (h)
          Tathiodon agilis (h)

#### Reed's Quarry 10
##### Dinosauria

    Saurischia
       Sauropoda
          Brontosaurus excelsus (h)

#### Reed's Quarry 11
##### Dinosauria

    Saurischia
       Sauropoda
          Apatosaurus amplus (h) (now Brontosaurus excelsus)
    Ornithischia
       Stegosauria
          Stegosaurus duplex (h) (now Stegosaurus ungulatus)

##### Mammalia

    genus and species indeterminant

#### Reed's Quarry 12 (Robbers' Roost Quarry)
##### Reptilia

    Testudines
       genus and species indeterminant
    Crocodylia
       Mesosuchia
          Goniopholis sp.

##### Dinosauria

    Saurischia
       Theropoda
          Allosaurus sp.
          Torvosaurus tanneri
          Coelurus sp.
          Fosterovenator churei
       Sauropoda
          Camarasaurus sp.
          Diplodocus sp.
    Ornithischia
    ornithopoda
       genus and species indeterminant
    Stegosauria
          Stegosaurus ungulatus (h)

#### Reed's Quarry 13
##### Reptilia

    Testudines
       Amphichelydia
          Glyptops plicatulus
    Crocodylia
       Mesosuchia
          Goniopholis sp.

##### Dinosauria

    Saurischia
       Theropoda
          Coelurus agilis (h) (part of Coelurus fragilis holotype)
          Coelurus fragilis (h)
    Saurischia
       Sauropoda
          ?Brachiosaurus sp.
          Camarasaurus lentus (h)
          Diplodocus sp.
    Ornithischia
       Ornithopoda
          Camptonotus dispar (h) (now Camptosaurus dispar)
          Camptosaurus medius (h)
          Camptosaurus nanus (h)
          Camptosaurus browni (h)
          Dryosaurus sp.
       Stegosauria
          Diracodon laticeps (h) (now Stegosaurus sp.)
          Stegosaurus sulcatus (h)
          Stegosaurus stenops
          Stegosaurus ungulatus

#### Reed Quarry 14
##### Dinosauria

    Saurischia
       Theropoda
          Allosaurus ferox (h) (now Allosaurus fragilis)