510 CENOZOIC TIME. 



(1.) Fishes, in the inferior shales, in the Green River basin (Middle Eocene). The 

 Gars, Lepidosteus glaber Mh., L. WhitneyiMh., Amia JYewberrianus Mh., A. depressus 

 Mh. ; the Teliosts, Clupea humilis L., Clupea pusilla Cope, etc. 



(2.) Reptiles. — Species of Emys, Trionyx, etc., among Testudinates; of Alligator, 

 Crocodilus, Diplocynodus, Limnosaurus, etc., among Crocodilians ; of Saniva (of Leidy), 

 Naocephalus (of Cope), Thirwsaurus grandis Mh. (seven feet long), Glyptosaurus prinr- 

 ceps Mh. (six feet long), among Lacertilians; Boavus occidentalis Mh., probably eight or 

 ten feet long, B. agilis Mh., B. brevis Mh., Lithophis Sargenti Mh., Limnophis o-assus 

 Mh., among Serpents. 



(3.) Birds. — An Owl, Bubo leptosteus Mh. ; the Woodpecker (?), Uintornis lucaris 

 Mh j the Waders, Aletornis nobilis Mh., A. gracilis Mh., etc. 



(4.) Mammals. — The Tapir-like Sthenorhines, Lophiodon Bairdianus Mh., Hyra- 

 chyus eximius L., H. princeps Mh., H. implicatus Cope, Limnohyus paludosus L., L. 

 diaconus Cope, Palasosyops levidens Cope, P. major L., P. laticeps Mh., very large; 

 Homacodon vagans Mh. Horned Sthenorhines (the horns in pairs), called Dinocerata 

 by Marsh, by whom the first species was described ; Uintatherium robustum L. Fig. 

 919, Dinoceras mirabile Mh., Tinoceras grande Mh. (Eobasileus pressicornis Cope), and 

 others. They are all referred to Uintatherium by Leidy. Colonoceras agreste Mh. 

 (as large as a Sheep) had but one pair of horns, and that on the nose. Possibly re- 

 lated to Hyrax, Anckippodus minor Mh., Tillotherium hyracoides Mh. Horse-tribe, 

 Orokippus pumilus Mh., 0. agilis Mh. (as large as a Fox). Carnivores, Mesonyx obtu- 

 sidens Cope (of the size of a large Wolf ), Limnqfelis ferox Mh. (nearly as large as a 

 Lion), Limnocyon riparius Mh. (as large as a Fox), Oreocyon latidens Mh. (about as large 

 as a Lion). Insectivores, Passalacodon litoralis Mh. (size of Hedgehog), Centetodon 

 pulcher Mb. (as large as a Mole), Centracodon delicatus Mh. (id.). Bats, Nyctitherium 

 velox Mh., N. priscum Mh. Quadrumana, Notharctus of Leidy; Limnoiherium, Thino- 

 lestes, and Telmaiolestes of Marsh, regarded as related to the Lemurs and Marmosets; 

 Tomithenum of Cope. Rodents, Sciuravus parvidens Mh., Colonomys celer Mh., 

 Paramys lejytodus Cope, P. robustus Mh., Pseudotomus Mans Cope, etc. Marsupials, 

 THacodon fallax Mh., T. grandis Mh., T. aculeatus Cope, Stypolophus pungens Cope. 

 Many other species have been described from the Rocky Mountain region. 



3. Yorktown Period, or Miocene. 



1. Mollusks. —In the marine beds of the Atlantic Border. —Fig. 901, Crepidula 

 costata Say; Fig. 902, inside view of the same; Fig. 903, Yoldia limatula Say, also 

 recent; Fig. 904, Callista Sayana Con.; Pecten decennarius Con. ; P. Virginianus Con. ; 

 Cardium Virginianum Con. ; Venus tridacnoides Con. ; V. capax Con. ; Chama corticosa 

 Con. ; Axinaa tumulus Con. ; Anomia Ruffini Con. ; also, among living species, Ostrea 

 Virginiana Gmelin, or common Oyster; Venus mercenaria Lam., or common Clam, 

 V. cancellata Gabb, Mactra (Mulinia) lateralis Say; Pecten concentHcus Say; Lunatia 

 heros Stimpson; Oliva litterata~La.m., Nassa (Tritia) trivittata Say, etc. 



In the marine beds of the Pacific Border. — Some of the species of California, as 

 given by Gabb, are Nassa fossat.a * Gould, Neveiita saxea Con., Cerithidea Califor- 

 nica* Hald., Turrit ella Hoffmanni Gabb, T. variata Con., Macheera patula* Cpr., 

 Tellina congesta Con., Lutricola, alta * Cpr., Lucina borealis* Linn., Yoldia imjiressa * 

 M., Pecten propatulus Con.; with the Echinoderms Clypeaster Gabbii Rem., Scutella 

 Gibbsii Rem. The Miocene of Oregon also contains various species. 



2. Vertebrates. — Fishes. — On the Atlantic Border. — Carcharodon megalodon ; 

 Galeocerdo latidens Ag. ; Hemipristis serra Ag. ; Oxyrhina hastalis Ag. In the Miocene 

 of Ocoya Creek, California, teeth of Sharks, of the genera EchinorMnus, Scymnus^ 

 Galeocerdo, Prionodon, ffemipi^istis, Carcharodon, Oxyrhina, and Lamna, besides a tooth 

 of a Zygobates. (Agassiz.) 



Reptiles. — In the Upper Missouri region. — Testudo Culbertsonii L., T. hemi- 

 spharica'L., T. Oweni L., T. lata L. 



Birds. — On the Atlantic Border. — Puffinus Conradi Mh., in Marjiand; Catarractes 



