'L I B UR.Y OF THE UNIVERSITY Of ILLINOIS REMOTE STORAq LIBRARY UNIVERSITY OF ILLINOIS URBANA Field Museum of Natural History Geology, Vol. IV, Plate XLVI PLASTRAL ASPECT OF Podocnemia olssoni, sp. nov., Type. X 2/5 Field Museum of Natural History Founded by Marshall Field, 1893 Publication 299 Geological Series Vol. IV, No. 8 A FOSSIL TURTLE FROM PERU BY Karl P. Schmidt ASSISTANT CURATOR OF REPTILES Oliver Cummings Farrington CURATOR, DEPARTMENT OF GEOLOGY EDITOR CHICAGO, U. S. A. September, 1931 PRINTED IN THE UNITED STATES OF AMERICA BY FIELD MUSEUM PRESS A FOSSIL TURTLE FROM PERU BY KARL P. SCHMIDT A fossil turtle represented by the nearly complete plastron and by an internal cast of the entire shell was presented to Field Museum of Natural History by Dr. Axel A. Olsson, geologist for the Inter- national Petroleum Company of Peru. This specimen was collected by Mr. Oscar Haught in the course of drilling operations near Mogollon, about twenty miles northeast of Negritos, in the oil field of northwestern Peru. Concerning the horizon, Dr. Olsson writes me that it was found in the Quebrada Mogollon, in certain shore-face sandstones of Middle Eocene age, belonging to the Salina Group, or to the lower part of the Clavilithes series of Bosworth's classification.1 The fossil in question formed the nucleus of a sandstone concretion about sixteen inches in length, of which one side had been split off, exposing the carapace, long before it was found. The fossilized shell material of the exposed side was entirely lost, leaving the somewhat weathered surface of the internal cast of the dorsal half of the shell. Fortunately, the remaining part of the concretion, when split open, disclosed the plastron intact, most of it attached to the outer part of the concretion, so that it is the inner surface of the shell that is exposed . The concretionary material encloses a few obscure molluscan remains. There is no difficulty in the identification of this turtle as to genus. The presence of very distinct mesoplastral bones, situated on the bridge between plastron and carapace, and widely separated from each other, refers it at once to the genus Podocnemis, of the family Pelomedusidae. The conformation of the plastral bones in general is much like that of the living Podocnemis sextubercidata as figured by Boulenger. Type material.— F. M. N. H. No. P 14172. From Mogollon, about twenty miles northeast of Negritos, Piura, Peru. Collected by Mr. Oscar Haught in 1927. Internal cast of carapace and plastron, with most of plastron intact, on the outer of the two pieces into which an originally single concretion has been split. 1 Iddings, Arthur and Olsson, A. A., Geology of Northwest Peru, Bull. Amer. Assoc. Petrol. Geol., Vol. XII, 1928, pp. 1-39, Plate 1, 3 figs. 251 252 Field Museum of Natural History — Geology, Vol. IV Horizon. — Shore-face sandstones of the Salina Group, Middle Eocene. Order Testudinata Oppel Family Pelomedusidae Cope Genus Podocnemis Wagler Podocnemis olssoni1 sp. nov. Plates XLVI and XLVII. Description of type. — Carapace oval, convex, its posterior margin flattened into a horizontal rim; costals 8; neurals apparently narrow; pygal nearly as long as wide. Plastron rounded in front, produced posteriorly into two subacute points which enclose a deep, symmetri- cally rounded emargination; front lobe of plastron broadly rounded, sides sloping toward the bridge; posterior lobe much longer, con- stricted just behind the bridge; eleven plastral bones; epiplastra with an abrupt angle in the middle of their hyoplastral border; entoplastron kite-shaped, instead of diamond-shaped as in P. sextuber- culata; mesoplastra irregularly six-sided, without acute inner angle, their inner angles well outside of the plastral border (if produced across the bridge) ; buttresses well developed; xiphiplastra with strong scar of pelvic attachment; external surface with fine vermiculate sculpture. Diagnosis. — Mesoplastral bones widely separated, situated on the bridge. Posterior lobes of plastron with deep emargination whose outline is nearly circular. Inner angle of the mesoplastrals well out- side the lateral contour of the plastral lobes, produced across the bridge. Nearest ally (suggested), the living P. sextuberculata of the upper Amazon region. Measurements MM. Length of carapace (approximate) 333.0 Width of cast of carapace 266.0 Length of plastron on mid-line 235.0 Total length of plastron 273.0 Width of plastron: at epiplastral-hyoplastral sutures 100.4 to inner angles of mesoplastra 179.0 at hypoplastral-xiphiplastral sutures 145.0 Plastral sutures and shields: epiplastral suture 14.1 length of entoplastron 50.6 hyoplastral suture 43.1 hypoplastral suture 61.2 xiphiplastral suture 55.3 hyo-hypoplastral sutures 87.3-87.3 length of mesoplastra 38.6-38.6 width of mesoplastra 40.4-41.6 1 Named for my old friend in laboratory and field, Dr. Axel A. Olsson, well known for his contributions to the paleontology of the American Tertiaries. A Fossil Turtle from Peru — Schmidt 253 Remarks. — Podocnemis olssoni appears to be more nearly allied to the living Podocnemis sextuberculata1 of the Amazon than to any of the extinct Eocene forms of other parts of the world. It is well distinguished from sextuberculata and other living forms by the relatively large size of the posterior lobe of the plastron. This character distinguishes it also from the Egyptian P. antiqua Andrews, of the Fayum. The sharply angulate epiplastral-hyoplastral suture and the more laterally placed mesoplastrals distinguish olssoni from P. fajumensis Andrews, also from the Egyptian Eocene.2 P. bower- banki of the London Clay has a very wide bridge, posterior emargina- tion of the plastron slight, and mesoplastra with acute mesad points.3 Fossil material referable to the genus Podocnemis was first reported from South America by Pacheco in 1913.4 He describes a fragment of a posterior lobe of a plastron from the apparently Cretaceous Bauru Formation at Barretos, Sao Paulo, southeastern Brazil, as Podocnemis harrisi. This species, from the opposite side of South America, differs radically from the new species in the shape of plastron as well as in the arrangement of the pelvic scars. The fragment of shell on which the Cretaceous Podocnemis harrisi is based is insufficient for final conclusion as to its generic identity. In naming the second extinct South American species of this genus, I take an especial pleasure in thus associating Dr. Olsson's name with that of Professor Gilbert Dennison Harris, for Olsson and the writer, equally with Pacheco, had the unforgettable privilege of association in field and laboratory with that inspiring teacher. The existence of Podocnemis in South America in Eocene time establishes it there as a contemporary of the Eocene species in Eng- land, India, Egypt, Malta and the Congo.6 As I interpret this distribution (together with that of the living species of the genus, which are confined to South America and Madagascar) in the light ^ydekker, Richard, Catalogue of the Fossil Reptilia and Amphibia in the British Museum (Natural History). Part III, Containing the Order Chelonia. London: Printed by Order of the Trustees, 1889, pp. 239, 53 figs. 2Andrews, C. W., A Descriptive Catalogue of the Tertiary Vertebrata of the Fayum, Egypt. British Museum (Natural History). London: Printed by Order of the Trustees, 1906, pp. xxxvil and 324, 26 pis. 3 Owen, Richard, Reptilia of the London Clay, Monogr. Paleontol. Soc, Vol. I, 1849, part 1, p. 70, pi. 23. 4 Pacheco, Joviano a d'Am.'1 Notas sobre a geologia do valle do rio Grande a partir da foz do Parde at6 a sua confluencia com o rio Parahyba (in Dourados, S. Jos§ Dos, Exploracao do Rio Grande e de seus affluentes). Relatorio Comm. Geogr. Geol. Sao Paulo, 1913, pp. 33-38, pis. 1-4. 8 The Paleocene form described by Dollo as Podocnemis congolensis has sub- sequently been referred to a distinct genus, Bantuchelys Dollo. 254 Field Museum of Natural History — Geology, Vol. IV of the Matthewsian scheme of dispersal from the northern hemi- sphere,1 the spread of the genus must have taken place before the late Mesozoic. I am unable to believe that "Gondwana land" or von Ihering's "Archhelenis"2 are necessitated as hypothetical land con- nections in the southern hemisphere by the distribution of this and other forms; but the occurrence of Podocnemis in the Eocene deposits of South America pushes the period of world-dispersal of these turtles far back into the Mesozoic. Matthew's hypothesis involves the supposition that Podocnemis reached South America by way of North America or from North America; and the discovery of fossil remains of this genus in North America may therefore be predicted as a necessary corollary of the thesis of Holarctic Mesozoic dispersal. 1 Matthew, W. D., Climate and Evolution. Ann. N. Y. Acad. Sci., Vol. XXIV, 1915, pp. 171-318, 33 figs. 2 Ihering, H. von, Les Mollusques f ossiles du Tertiare et du Cretace Superieure de l'Argentine, An. Mus. Nac. Buenos Aires, Vol. VII, 1907, pp. 1-576, pis. 1-17. Field Museum of Natural History Geology, Vol. IV, Plate XLVII CARAPACIAL ASPECT OF Podocnemia olssoni, sp. nov., Type. X 2/5 LIBRARY UNIVERSITY OF ILLINOIS URBANA INDEX Abbott, J. B. 17, 26, 36, 38 Acanthaspis 165 Acanthias 157 Acanthodians (Acanthodes, Acanthods) 163, 164, 177, 188, 189 Acipenser 95, 106, 123 Acipenserids 143, 162 Acrorhabdus 162 Actinopterygii (Actinopterygians) 140, 161, 187 Alligator 226 sinense 223, 226 ihomsoni 223, 226 Alligatoridae 223 Allognathosuchus 223, 225, 226 heterodon 223, 225 mooki 223, 224, 225 polyodon 223, 224, 225 riggsi Patterson sp. nov. 223, 224, 225, 226 wortheni 225 Amazon region 252, 253 Amia 106, 147, 162 Amiadae 187 Amphibiceras 58 bicornis 59 circullus 60 clermontensis Slocom sp. nov. 59, 60 rhinoceros Slocom sp. nov. 58, 59 Amynodon 17, 21, 23, 25 intermedius 23 Amynodon beds (Horizon B of Peter- son and Osborn) 22, 25, 26, 31, 32, 33, 35, 38, 41 sandstone 22, 23, 33 Ancyrocrinus 204 bulbosus 204 spinosus 204 Antiarcha 189 Appel, J., acknowledgment to 231 collector 229 Archhelenis 254 Arctolepis (= Acanthaspis) 165 Arthrodira (Arthrodires) 95, 96, 119, 132, 137, 146, 150, 164, 167, 174, 176, 181, 182, 184, 185, 187, 188 Arthrodires, certain remarks concerning the other non-Macropetalichthyid 164 concluding remarks on the affinities of 187 some general remarks on the non- Macropetalichthyid 186 Asaphidae 47 Asaphus 56, 61 expansus 48 Atrypa reticularis 87 Axonophora 245 Banffia 241 Bantuchelys 253 congolensis 253 Bauru formation 253 Becker, A. G., acknowledgment to 83 Beecher, C. E., quoted 61 Bertie waterlime 241, 247 Bertiella 241 obesa 241 Birgeria 162 Black River formation 64 Borden, W. W., collector 203, 204, 205, 212 Bridger formation 18, 26, 31, 40, 223 Bumastus 54, 56 beckeri Slocom sp. nov. 54, 56 billingsi 56 orbicaudalus 55, 56 Burlington group 205 Caimanoidea 226 Calmonia (?) sp. 213 Calymene 66 christyi 68 fayettensis Slocom sp. nov. 67, 68, 70 gracilis Slocom sp. nov. 69 mammillata 68, 70 niagarensis 68 severia 68, 70 Calymenidae 66 Cambrian 201, 241 Cambrian, Lower 208, 210 Carboniferous 162 Cassidulidae 9 Cassidulus 5 abruptus 14 aequorus 7 hemisphericus Slocom sp. nov. 7, 15 intermedius Slocom sp. nov. 3, 6, 7, 14, 15 micrococcus 7 subconicus 14 subquadratus 5 Cephalaspids 161, 188 Ceratodus 113, 162, 163 Ceraurus 70 dentatus 74 elginensis Slocom sp. nov. 73, 74 milleranus 71, 74 pleurexacanthus 71, 73, 74 Chasmops 64 Cheiruridae 70 Chelonichthys primigenius 170 Chelyophorus 170 Chert bed (Niagaran) of Hamilton, Ontario 237 Chimaera 111 monstrosa 102 255 256 Field Museum of Natural History — Geology, Vol. IV Chimaeroids 97, 181, 184 Chimaeropsis 188 Chlamydoselache 189 Chlamydoselachus 130, 140, 157, 160, 161, 187, 188 Chondrosteids 162 Cincinnati shales 54 Classification and terminology of tri- lobites 44, 45, 46 Clavilithes series 251 Coccosteids, the 164, 168, 170, 172, 173, 176, 177, 179, 180, 181 dentition of 176 dermal bones of the cheek of 173 dermal cranial roof of 172 primordial neurocranium of 170 sensory canals of the head of 177 some general remarks on 180 some remarks on the trunk and the fins of 179 Coccosteus 137, 147, 170, 171, 176, 179, 180, 181 decipiens 172, 173, 174, 177, 178, 179 Cochliodontids 188 Coelacanthidae (Coelacanthids) 162, 172 Conrad, T. A., quoted 5, 56 Conularia 229, 231, 234, 239 tenuis 239 Corniferous (Onondaga) limestone 37 Cretaceous 1, 5, 9, 12, 253 Crocodilia 223 Crocodilus 23 Crossopterygii (Crossopterygians) 140, 161, 162, 179, 187 Cryphaeus 213 australis 213, 214 nicholsi Roy sp. nov. 214 Cryptonymus 61, 211 schlotheimi 61 variolaris 211 Cybele 63 grewingki 64 kutorgae 64 revaliensis 64 Cybeloides Slocom gen. nov. 63 ella 63, 64 iowensis Slocom sp. nov. 63, 64 prima (valcourensis) 63, 64 winchelli 63, 64 Cyclostomes 161 Dactylethra conspicua 246 Dahlgren, B. E., acknowledgment to 231 Dalman, J. W., quoted 52 Dalmanites 64 Degeneration in degree of ossification in skeleton of teleostomous fishes 161, 162, 163 De Losch, E., acknowledgment to 231 collector 229 Dendrograptidae 242 Dendroidea 242 Desmograptus 245 micronematodes 244 Desor, S., acknowledgment to 16 Devonian 162, 180, 182, 186, 207, 208, 213, 214 Lower 181, 203 Middle 87, 205, 208 Upper 152, 163, 181 Dictyonema 242 crassibasile (?) 243 retiforme 242 tenellum 243 Dinichthys 137, 170, 171, 172, 173, 176, 177, 183 gouldi 179 halmodeus 175 intermedins 174 terrelli 172 Dinomylostoma 181 Diplocarcides 162 Diplognathus 176 Dipnoi (Dipnoans) 140, 161, 162, 187 Dipterus 162, 163 Discinacea 246 Discinidae 246 Dolichorinae 25 Dolichorinus 17, 21, 24, 25, 26, 31, 34, 35, 40, 41 cornutus 31, 32, 34, 35 fluminalis Riggs sp. nov. 21, 33, 34, 35,36 hyognathus 31, 32 intermedins 32, 33, 34 longiceps 20, 21, 32, 34, 35 Duncan, P. M., acknowledgment to 16 Eccoptochile 75 meekanus 75 Echinoids, terminology of 2, 3, 4 Economy formation 240 Elasmobranchii (Elasmobranchs) 118, 127, 129, 130, 131, 140, 147, 156, 157, 159, 161, 163, 164, 168, 177, 179, 185, 186, 187, 188, 189 osseous skeleton originally in 163, 164 Encrinuridae 61 Encrinurus 61 pernodosus Slocom sp. nov. 61 sexcostatus 63 variolans 63 Eobasileus 17, 20, 24, 25 Eocene 5, 253, 254 Middle 223, 251, 252 Epipetalichthys Jaekel gen. nov. in Stensio 129, 131, 132, 149, 188 cavum cerebrale of 157 dermal bones of the cranial roof of 157 ethmoidal region of 156 labyrinth and orbitotemporal region of 155 Index 257 microscopic structure of the bone of 153 occipital region of 154 primordial neurocranium of 152 remarks on 160 sensory canals of the head of 158 vnldungensis Jaekel sp. nov. in Stensio 91, 152, 154, 158, 163, 184 Epitrachys 241 Erronomenosteus 174, 176 Espenshade, E., acknowledgment to 231 collector 229 Eucalyptocrinu8 203 bordeni Roy sp. nov. 203 elrodi 204 Farrington, Oliver C, editor's prefaces 87, 229 acknowledgment to 201, 231 Fauna of Ripley group 14, 15, 16 Favosites 203 cariosus ( =limitaris) 203 limitaris 203 Fayum 253 Fisher, D. J., acknowledgment to 231 collector 229 Fishes, degeneration in degree of ossi- fication in skeleton of teleostomous 161, 162, 163 Fossils in the Lower Uintah, range and occurrence of 22, 23, 24, 25 Galena limestone 64 Galena, specimens of Nileus vigilans 53 Gephyrea (Gephyrean) 241, 242 Gilsonite, fissure deposit of, in White River Canyon, Utah 19, 22 Glossophonia 240 Goff, J., acknowledgment to 16 Goldring, W., acknowledgment to 201 Golfingia 242 Gondwanaland 254 Graptolitoidea 242 Green River series 19 Gregory, W. K., acknowledgment to 41, 92 Griffith, S., acknowledgment to 231 collector 229 Gronemann, C. F., acknowledgment to 201 Gyracanthides murrayi 216 Hamilton beds 205 Harpagolestes 17, 21, 24 Harris, G. D., tribute to 253 Harrodsburg limestone 206 Haught, O., collector 251 Hemiaster 9 dalli 11 lacunosus Slocom sp. nov. 10, 11 parastatu8 9, 10 Heptanchu8 140 Hirudinea 241 Holmgren, N., acknowledgment to 138 Holocephali 188, 189 Homosteids, the 164, 180 Homostem 180 Hybodus 189 Hyolithes 208 americanus 208 welleri Roy sp. nov. 208 Ilaenus 56, 61 Incertae sedis (Vermes) 246 Isoteliis 47 gigas 47, 48, 49 iowensis 47, 48, 49, 50 maximus 47, 49, 50 megistos 48 Isotelus Zone 50 Ithaca sandstone (beds) 208, 210 Jaeckel, O., acknowledgment to 91, 92, 182 Jagorina 186 pandora 182, 183, 184, 185, 186, 188 Jagorinids, the 182 abdominal armour of 185 dentition of 185 dermal bones of the cheek of 185 dermal cranial roof of 184 primordial neurocranium of 182 sensory canals of 185 visceral skeleton of 185 Junkermann, S., acknowledgment to 91, 150 Jurassic, Lower 162 Kay, G. F., acknowledgment to 83 Kinderhook group 215, 216, 218, 220 Laemargus 169 borealis 132 Lafayette group 1 Lecthaylus 236, 237, 238, 239, 240, 241, 242, 245, 246 gregarius 229, 231, 233, 234, 235, 237, 238, 239, 240, 242, 245, 246 Legnodesmus 246 Leidy, J., quoted 217 Lepidosteus 106 Leptaena rhomboidalis 87 Letl, F. H., acknowledgment to 231 collector 229, 243, 244, 245 Lichadidae 58 Liljevall, G., acknowledgment to 92 Link, T. A., acknowledgment to 231 collector 229 Linthia 9, 11 tumidulm 14 variabilis Slocom sp. nov. 2, 12 Lithographic limestone, Solenhofen 241, 246 258 Field Museum of Natural History— Geology, Vol. IV Lockport group 247 Shale, Upper 243, 244, 245, 246, 247 Upper 237 London Clay 253 Loricati 103, 113 Lower Cambrian 208, 210 MacClintock, P., acknowledgment to 231 collector 229 Macropetalichthyids 160, 161, 163, 164, 165, 167, 171, 172, 173, 180, 186, 187 some general remarks on the 160 Macropetalichthys 87, 119, 132, 145, 150, 158, 187 agassizi (?) 91, 150, 151, 154, 159 pelmensis 142, 143, 152, 159 rapheidolabis 91, 92, 94, 97, 101, 102, 103, 104, 107, 110, 111, 113, 114, 115, 117, 123, 124, 125, 127, 128, 130, 132, 133, 136, 137, 139, 141, 142, 144, 146, 150, 151, 152, 153, 154, 155, 156, 157, 158, 159, 163, 165, 169, 170, 182, 183, 184 cavum cerebrale cranii and brain of 134 dentition of 146 dermal bones of the cheek of 143 dermal bones of the primordial neurocranium of 140 ethmoidal region of 129 labyrinth cavity of 116 labyrinth region of 103 occipital region of 95 orbitotemporal region of 119 primordial neurocranium of 92 remarks on 150 sensory canals of the head of 146 visceral skeleton of 144 Maquoketa beds 43, 47, 53, 71 Lower 43, 47, 50, 52, 54, 56, 57, 59, 60, 63, 66, 69, 73, 75, 77, 79, 81, 83 Middle 43 Upper 43, 47, 57, 70 of Fayette County, Iowa, new trilo- bites from the 42 Matthew, W. D., acknowledgment to 92 Megalaspis 50 beckeri Slocom sp. nov. 50, 52 belemnura 52 extenuata 52 gonioceras 51 Megalomus 207 canadensis 207 Mehl, M. G. 17, 33 Menaspis 188 Mesatirhinus 17, 25, 26, 36, 39, 41, 42 megarhinus 26 petersoni 39 Mesatirhinus superior Riggs sp. nov. 21, 24, 26, 39, 41 Mesonyx 17, 20, 24 Mesozoic 189, 254 Metarhinus 17, 19, 21, 24, 25, 26, 27, 29, 30, 36, 37, 38, 39, 40, 41 cristatus Riggs sp. nov. 20, 28, 30 diploconus 27 earlei 20, 21, 27, 29, 30, 34 fluviatilis 22, 23, 27, 28, 29, 30 riparius Riggs sp. nov. 20, 21, 27, 28, 29,30 Metarhinus beds (Horizon A of Peter- son and Osborn) 22, 23, 27, 28, 29, 35, 36, 37 sandstone 22, 26 Zone, Lower 19, 20, 21, 23, 27, 28 Upper 19, 20, 21, 24, 25, 27, 28, 29, 33,36 Micraster 9 Middle Eocene 251, 252 Mississippian 201, 205, 215, 220 Molluscoidea 246 Monograptidae 245 Monograptus 245 vomerinus 238, 245 Murchison, R. I., quoted 54 Mustelus 157 Mylostoma 180 Mylostomids, the 164, 180, 181 Myolina 206 sappenfieldi Roy sp. nov. 206 Myriacanthus 188 Nawn, H., donor 210 Nawnites Roy gen. nov. 208 gilboensis Roy sp. nov. 209 Neotremata 246 Nereites 210 Newbury, J. S., quoted 215, 216 Niagara limestone 43 Niagaran 204, 207, 212, 237, 243, 244, 245, 246, 247 Nichols, H. W., acknowledgment to 91, 92 231 collector 207, 208, 213, 214 Nileus 52 vigilans 51, 52 Niobe 212 huberi Roy sp. nov. 212 lineolata 212 morrisi 212 Non-Macropetalichthyid Arthrodires 137, 186 certain remarks concerning the other 164 some general remarks on 186 Normanskill shale 213 Notidanidae 144 Oligocene, Lower 223 Oligochaeta 240 Index 259 Olsson, A. A., donor 251 Onchnisoma 242 Onondaga (Corniferous) limestone 87 Opisthoparia 47 Oracanthus 215, 216, 217, 218, 219 farringtoni Roy sp. nov. 219 vetustus 215, 219, 220 Orbiculoidea 246 molina 247 sp. 246 Ordovician 43, 50, 52, 61, 63, 77, 99 Middle 213 Osborn, H. F., acknowledgment to 41 Ostrocoderms 161, 187, 188 Ottoia 241 Owen, D. D., quoted 48 Pachyosteus 170 Palaeodiciyota 244 bella 244 Palaeoneilo 207 fieldi Roy sp. nov. 207 rhysa 207 Palaeoniscidae 187 Palaeoniscids 162 Palaeozoic 164, 189, 201, 240 Paleocene 253 Patterson, B., acknowledgment to 231 collector 229, 243, 244, 245 Pelomedusidae 251, 252 Perichaetidae 240 Peru, a fossil turtle from 251 Petalosoma 242 Peterson, O. A., acknowledgment to 41 Phacopidae 79 Phacopina 214 devonica 214 Phacops 214 salteri 214 Phascolion 242 Phlyctenaspids, the 164, 165, 167, 168, 169, 177, 178, 180 dermal covering of the trunk of 169 dermal cranial roof of 167 primordial neurocranium of 165 sensory canal system of the head of 168 Phlydenaspis 165, 172, 173 acadica 165, 166 Pholidosteus 170, 174, 17 friedelii 170, 175 Platteville, beds 57 Platyceras 207 daviesi Roy sp. nov. 207 sp. A 208 sp. B 208 Pleuracanthns 189 Podocnemis 251, 252, 253, 254 antiqua 253 bearing of on theory of Holaratic dispersal 253, 254 bowerbanki 253 Podocnemis congoliensis ( = Bantuchelys congoliensis) 253 fajumensis 253 geographical and geological distribu- tion of 253, 254 harrisi 253 olssoni Schmidt sp. nov. 252, 253 sextuberculata 251 Polyodon 95, 107, 123 Polyodontids 143, 162 Polypterus 106, 113, 127 Post-Carboniferous forms (Dipnoi) 162 Post-Devonian forms (Dipnoi) 162 Poteriocrinus 205 robbi Roy sp. nov. 205 Proparia 61 Protelotherium 17, 21, 25 uintense 23 Protoscolex 240, 245 batheri 240, 246 latus 246 ruedemanni Roy and Croneis sp. nov. 245 Protylopus 21, 23, 25 Pterygometopus 79 callicephalus 81, 83 fredericki Slocom sp. nov. 79, 81 intermedins 83 larrabeei Slocom sp. nov. 81, 83 Puerco formation 223 Pycnodonts, the 164, 170, 181, 182 Quebec group 52 Racine formation 237 Raja 118 Range and occurrence of fossils in the Lower Uintah 22, 23, 24, 25 Raymond, P. E., acknowledgment to 213 Recent period 9, 12 Rhadinorhinus Riggs gen. nov. 17, 24, 25, 36, 37, 39, 41 abbotti Riggs sp. nov. 20, 36, 37, 39 diploconus 37, 39 Rhamphodus 181, 182, 185 Richmond beds 77 Riggs, Elmer S., acknowledgment to 223 collector 223 Ripley formation (group) 1, 7, 8, 10, 11, 14 group, fauna of 14, 15, 16 of Mississippi, new echinoids from the 1 Robb, Mrs. G. W., donor 203, 205 Romer, A. S., acknowledgment to 218 Roy, Sharat K., collector 208, 210, 213, 229 Ruedemann, R., acknowledgment to 213, 231 quoted 239 260 Field Museum of Natural History — Geology, Vol. IV St. John, O. H., and Worthen, A. H., quoted 217, 218 St. Louis limestone 215 Salina group (South American Eocene) 251, 252 Sappenfield, G. BM acknowledgment to 207 collector 206 Saurichthyidae (Saurichthyids) 162, 187 Saurichthys 95, 107, 123, 127, 130, 143 Scaumenacia 162 Schmidt, K. P., acknowledgment to 223 Scyllicum 118 Seaweed 237, 246 Selachii (Selachians) 106, 113, 114, 115, 117, 118, 126, 130, 133, 145, 160, 161, 184, 185, 187, 189 Selenosteus 170 Serpulites 229, 231, 234, 238, 239, 246 Silurian 61, 229, 240, 242 Siluroids 123 Sipunculoidea 241, 242 Sipunculus nudus 242 Slocom, A. W., acknowledgment to 231 collector 229 Snake Creek beds 223 Solenhofen limestone 241, 246 Spatangidae 9 Spatangoidea 5 Sphaerocoryphe 77 granulata 77, 78 maquoketensis Slocom sp. nov. 77, 78, 79 salteri 78 Sphenocoelus 19 uintensis 23 Stegocephalians 169, 179 Stenosteus 173 Sthenodectes 18, 21, 25, 38, 39 incisivum 23, 38, 39 Sturgeon 144, 184, 186, 187 Stylinodon 17, 21, 23, 25 Teleostei 107 Teleostomi (Teleostomes, teleostomous fishes) 114, 133, 142, 145, 164, 175, 176, 179, 182, 188 Teleostomous fishes, degeneration in degree of ossification in skeleton of 161, 162, 163 Telmatherium 31 diploconum (=Rhadinorhinus diplo- conus) 37 megarhinum ( =Metarhinus flumina- lis) 22 Terminology of echinoids 2 Tertiary 1 Tetrapods 182 Thaleops 56 ovata 56, 57 Titanichthys 137, 166, 170, 173, 176 agassizi 143 Titanotheridae 17 Titanotherium beds 223, 226 Trematia spinosa 247 Trenton limestone 56, 64, 81 specimens of Nileus vigilans 53 Triassic, Lower 162 Trilobites from the Maquoketa beds of Fayette County, Iowa, new 42 terminology and classification of 44, 45,46 Triplopus 17, 24 Triton 169 Tubicola 239 Turtle from Peru, a fossil 251 Tylosoma 242 Uintah beds, formation of 18, 19, 29, 30, 32, 35, 40, 41 formations of new or little known titanotheres from the Lower 17 group 17, 18 Lower (Horizon A of Peterson and Osborn), 18, 20, 26, 27, 31, 32, 35 range and occurrence of fossils in the Lower 22, 23, 24, 25 Upper (Horizon C of Peterson and Osborn) 25, 30, 40 Uintatherium 17, 21, 23, 25 Upper Lockport group 237 Vermes 245 Wanneria walcottanus 210 Wasatch formation 223 Washakie formation 18, 26, 27, 29, 31, 40 Weller, S., acknowledgment to 83, 229, 231 quoted 66, 70, 71, 233, 234 Wenlock limestone 63 shale 212 Wilcox group 1 Worthen, A. H., and St. John, O. H. , quoted 217, 218 Xenacanthus 189 Nature vey Libr tr v