GEOLOGIC DISTRIBUTION 



Lower Oligocene — Continued 



Cypress Hills — Merycoidodon culbertsonii, 



M. sp. 

 Pipestone — Bathygenys alpha 



Middle Oligocene 



Brule (lower) — Eporeodon bullatus, E. dkk- 

 insonensis, E. montanus, Merycoidodon 

 affinis, M. culbertsonii, M. c. periculorum, 

 M. gracilis, M. macrorhinus, M. platy- 

 cephalic 



Upper Oligocene 



Brule (upper) — Eporeodon die kins onensis, 

 E. major, E. m. hybridus, E. socialis, 

 Eucrotaphus jacksoni, Leptauchenia decora, 

 L. major, L. nitida 



John Day (middle) — Eporeodon bullatus, 

 E. condoni, E. leptacanthus , E. longifrons 

 per bullatus, E. accident alis, E. pacificus, 

 E. parvus, Oreodontoides oregonensis, 

 Paroreodon marshi, Pr ornery cochoerus cur- 

 videns, P. lulli, P. microcephalus 



Martin Canyon (lower) — Eporeodon major 

 cedrensis 



Sespe (basal upper) — Eporeodon thurstoni 



Toston — Eporeodon helence 



Lower Miocene 



Gering — Cyclopidius densus 



Harrison (lower) — Eporeodon major cheeki, 

 Leptauchenia minora, Merychyus harri- 

 sonensis, M. siouxensis, M. sp., Merycoides 

 cursor, M. latidens, Mesoreodon chelonyx, 

 M. intermedius, M. megalodon, M. scotti, 

 M. sp., Promerycochcerus carrikeri, P. 

 gregoryi loomisi, P. hollandi, P. h. hatcheri, 

 P. h. minor, P. montanus grandis, P. van- 

 tasselensis, Ticholeptus petersoni 



Harrison (upper) — Merychyus arenarum, 

 M. a. leptorhynchus, M. a. minimus, M. 

 sp., Merycochcerus magnus, M. sp., Meso- 

 reodon sp. 



John Day (upper) — Eporeodon longifrons, 

 E. I. perbullatus, E. pacificus, E. trigono- 



Lower Miocene — Continued 



John Day (upper) — Continued 



cephalus, Oreodontoides oregonensis, Pro- 

 merycochcerus chelydra, P. c. latidens, P. 

 leidyi, P. macrostegus, P. m. infiatus, P. 

 marshi, P. superbus 



Monroe Creek — Leptauchenia decora, Meso- 

 reodon megalodon, Phenacoccelus mun- 

 roensis, P. typus 



Rosebud (lower) — Cyclopidius densus, C. 

 lullianus, Eporeodon major relictus, Lep- 

 tauchenia major, L. nitida, Merychyus 

 curtus, Mesoreodon megalodon, M. sp., 

 Promerycochcerus gregoryi, P. thomsoni, 

 P. vantasselensis pygmceus 



Rosebud (upper) — Merychyus delicatus, M. 

 sp., Merycochcerus matthewi, M. sp. 



Sespe (upper) — Cyclopidius calif ornicus, 

 Promerycochcerus hesperus 



Tecuya — Promerycochcerus erythroceps 



Middle Miocene 



Brown's Park — Ticholeptus sp. 

 Cuyama — Merycochcerus sp. 

 Hayden's Bed D — Merycochcerus proprius 

 Sheep Creek — Cyclopidius (C.) schucherti, 

 Merychyus sp., Pronomotherium siouense 



Upper Miocene 



Barstow — Merycochcerus buwaldi 



Deep River — Cyclopidius simus and associated 

 species, Merychyus pariogonus, Merycoides 

 longiceps, Promerycochcerus montanus, 

 Ticholeptus brachymelis, T . zygomaticus 



Flint Creek — Poatrephes paludicola, Ticho- 

 leptus bannackensis, T. breviceps, T. smithi 



Hayden's Bed F — Merychyus elegans,Meto- 

 reodon major, M. medius 



Madison Valley — Metoreodon compressidens, 

 Pronomotherium altiramus, P. elrodi, P. 

 laticeps, P. madisonium 



Mascall — ? Merycoidodon sp., Merycochce- 

 rus sp., Ticholeptus obliquidens, T. sp. 



Mint Canyon — Merychyus sp. 



Pawnee Creek — Merychyus elegans paniensis, 

 M. sp., Merycochcerus proprius, Ticholep- 

 tus rusticus 



