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Fossil frogs of North America have been reviewed by Holman (2003), and records from the middle and late Miocene of North America are relatively numerous. Nonetheless, frog fossils from the late Miocene Clarendonian North American Land Mammal Age time period (ca. 12.5-9 Ma) are rare and biogeographically poorly represented. There is a single record of a bufonid from the Clarendonian Land Mammal Age (LMA) of South Dakota (Holman, 1973), but most of our knowledge of Clarendonian LMA frogs comes from a single local fauna, the Wakeeney Lo cal Fauna (L.F.) of Kansas (Wilson, 1968; Holman, 1975, 2003). In this report we describe an important collection of middle to late Clarendonian (ca. 11-9 Ma; time scale of Woodburne, 2004) frog fossils recovered from the Whisenhunt Quarry fossil site of Beaver County, Oklahoma. The mammals of the Whisenhunt Quarry fossil site have been discussed previously by Dalquest et al. (1996) and, to a lesser degree, by Smith (2005). The Whisen hunt Quarry frogs represent the first lower vertebrates reported from the local fauna, but more importantly they provide new and noteworthy information that improves our knowledge about the diversity and distribution of North American midcontinental frogs from this time period. Fossil Locality?The Whisenhunt Quarry fossil site is located approximately 10 km south of Gate, Beaver County, Oklahoma, in the Laverne Formation at T3N, R28E, Sec. 9, SE 1/4, NW 1/4 (Dalquest et al., 1996; see Fig. 4 for the general location of the site). Late Miocene mammals from this Great Plains formation have been known to science since at least the late 19th century (see discussion in Tedford et al, 2004). Fossils from the Whisen hunt Quarry site were obtained by Dalquest et al. (1996) by pro cessing matrix collected at the quarry in the early 1990s. The ma terial was derived from a stratum of sand and diatomaceous clay, which they (Dalquest et al., 1996:133) believed represented an ancient "still-water pool or lake in a marsh or swamp." No ra diometric date (numerical date) is available for the Whisenhunt Quarry, but on the basis of a detailed study of the Whisenhunt Quarry mammals, Dalquest et al. (1996) assigned the local fauna a biochronological age of middle to late Clarendonian LMA. They suggested that the Whisenhunt Quarry L.F. best correlated with the well-documented late Clarendonian Wakeeney L.F. of Kansas. On the basis of megaand micromammal components of the Whisenhunt Quarry and mammals from other nearby Lav erne Formation sites, Tedford et al. (2004) suggested a medial Clarendonian age for the local fauna.

The painted turtle, Chrysemys picta, and the snapping turtle, Chelydra serpentina, occur in aquatic habitats north of Lake Superior in boreal forest and cold prairie areas across Canada, and have by far the most northern range of any modern North American chelonian taxa. These two species are also the dominant turtles of the North American Pleistocene glacial ages and were among the first species to invade formerly glaciated areas at the end of the Wisconsinan. These Pleistocene occurrences are documented here. Several remarkable behavioral, physiological and reproductive adaptations that may act together to allow these species to survive in such northern areas are discussed.

We report the earliest fossil record of a Pigmy Rattlesnake (Sistrurus) on the basis of a trunk vertebra from the Late Miocene (Clarendonian NALMA) Pratt Slide local fauna of Nebraska. Vertebral characteristics of the genus are discussed, and the fossil was diagnosed mainly by the presence of a zygosphenal spine. This record suggests Sistrurus existed as a distinct lineage prior to the Late Miocene and that the genus has been present on the central Great Plains for at least five million years.

Anuran maxillary, squamosal, and ilial elements from the Late Eocene of Hampshire and the Isle of Wight in southern coastal England represent a new species, Thaumastosaurus wardi, of this previously monotypic genus. Teeth, represented for the first time in the fossil record of this genus, are of the pedicellate type but appear to have specialized swollen tooth crowns. Based on the unique pit and ridge sculpturing of the cranial bones, the pedicellate teeth, and ilial characters of Thaumastosaurus, the genus resembles the leptodactylid genus Caudiverbera (Telmatobiinae) of the modern fauna of Chile and the Miocene of Argentina. It is suggested, however, that Thaumastosaurus should be considered of uncertain familial relationships (familia incertae sedis) until adequate material becomes available.

New material of Emydoidea hutchisoni from Nebraska shows the species lived in the North American Miocene from medial Barstovian (approximately 14.5–13 million BP) to Clarendonian (approximately 11.5–9 million BP) times. Previously unknown plastra, limb girdle elements, and limbs of E. hutchisoni have provided new characters that have led to a revised diagnosis of the species. Derived characters shared by E. hutchisoni and Emydoidea blandingii include an elongated nuchal bone, ovoid plastral shape, short and broad femoral scute overlap, very wide xiphiplastral shelf, xiphiplastral striations, and an angular coracoidal border. But E. hutchisoni is distinct from E. blandingii in being smaller and having an akinetic shell with a shorter nuchal area, and it probably was more aquatic. The plastral lobes of a complete E. hutchisoni plastron are firmly fused together by dovetail sutures and a second, less complete plastron, has dovetail sutures on the anterior surface of the hypoplastron. Moreover, the p...

Quarrying in east-central Indiana has uncovered richly fossiliferous unconsolidated sediment buried beneath Pleistocene glacial till. The fossiliferous layer is part of a sedimentary deposit that accumulated in a sinkhole developed in the limestone flank beds of a Paleozoic reef. Plant and animal (mostly vertebrate) remains are abundant in the fossil assemblage. Plants are represented by a diversity of terrestrial and wetland forms, all of extant species. The vertebrate assemblage (here designated the Pipe Creek Sinkhole local fauna) is dominated by frogs and pond turtles, but fishes, birds, snakes and small and large mammals are also present; both extinct and extant taxa are represented. The mammalian assemblage indicates an early Pliocene age (latest Hemphillian or earliest Blancan North American Land Mammal Age). This is the first Tertiary continental biota discovered in the interior of the eastern half of North America.

A well-preserved skeleton of a leopard frog (Rana pipiens) was recovered from a calcareous nodule collected near Eardley, Quebec. Such nodules from the Ottawa area evidently date to the Ottawa Delta phase of the Champlain Sea, ca. 10 000 BP, and may contain remains of fishes, birds, mammals, marine mollusc shells and other invertebrates, and plants. Palynological analysis of matrix from the specimen suggests either (1) that forest communities were prominent in the area where the frog lived, or (2) that, presuming the specimen was from a large body of water, the environment supported herb and shrub tundra communities with only a few trees. This is the first record of an amphibian from Champlain Sea deposits. The specimen indicates the presence of grassy meadows near the seacoast.

Middle and late Hemphillian (late Miocene) snakes from Nebraska were identified and interpreted. The mid-Hemphillian (ca. 7 Ma) Lemoyne Quarry of Keith Co., SW Nebraska yielded at least two boid, thirteen colubrid and two viperid snakes. The late Hemphillian (ca. 5 Ma) Devils Nest (Knox Co.), Santee (Knox Co.), and Mailbox Prospect (Antelope Co.) sites of NE Nebraska together yielded at least nine colubrids and one viperid snake. Twenty-four percent of the 16 mid-Hemphillian snake genera and 67% of the 12 species are extinct. Of the 9 genera and 7 species of late Hemphillian snakes, only Paleoheterodon tiheni is extinct. A snake from Lemoyne Quarry is described as new (Arizona voorhiesi). With this new information, the fossil record of Arikareean through Blancan (Miocene through Pliocene) snake genera from midcontinental North America suggests erycinine boids became extinct across the region by late Hemphillian time, and colubrid snakes became generically modern by early Blancan time. These event...

The remains of a frog (Rana pipiens) and two turtles (Chrysemys picta and Clemmys insculpta) were recovered from an organically rich clay matrix in association with mastodon remains in Halifax County near East Milford, Nova Scotia. Preliminary stratigraphic studies and radiometric dating indicate an Early Wisconsinan age between 70 000 and 80 000 BP for the site. All of the herpetological species are cold-tolerant forms that inhabit Nova Scotia today. The turtles are important paleoclimatically, in that they suggest that the summers had a sufficient number of warm days for the successful incubation of their eggs. Together, the herpetological species indicate a quiet, well-vegetated pond or small lake, with peripheral meadows, and the presence of a meandering stream with sand or gravel banks.

Triturus vulgaris (smooth newt), Triturus helveticus or T. vulgaris (palmate or smooth newt), Triturus sp. (newt), Pelobates fuscus (common spadefoot), Bufo bufo (common toad), Bufo calamita (natte...

Late Quaternary herpetological records from the Central Great Lakes States of Michigan, Illinois, Indiana and Ohio allow for reflections on reinvasion of herpetological species into previously uninhabitable areas, as well as some comments on paleoclimate. Advances of the Wisconsinan Laurentide ice sheet obliterated herpetological habitat in all of Michigan as well as much of Illinois, Indiana and Ohio; it also restricted herpetological habitat in the southern parts of the three latter states. By about 15-14 ka BP a rich herpetofauna, similar to the one that occurs in the area today, and suggesting a moderate climate, occurred in southwestern Indiana. Turtle faunas in central Indiana (13-12 ka BP) and west-central Ohio (11-10 ka BP) suggest that warm summer climates existed in those areas at the time. On the other hand authentic reptile records are unknown from the Pleistocene of Michigan, and considering the pollen record, that state probably had a much colder climate during postglacial Late Wisconsinan times. A well-developed turtle fauna associated with temperate deciduous forest occurred in southern Michigan about 6 ka BP, and a rich herpetofauna, similar to the one that occurs in the area today, occurred in southwestern Indiana about 4 ka BP. This evidence suggests the possibility that the herpetological reinvasion of the Central Great Lakes region might have been nearly complete by Mid-Holocene times.

Freshwater/estuarine organic deposits at Cudmore Grove, Mersea Island, Essex, England, palynologically dated to the Hoxnian Interglacial Substage Ho IIIb, have yielded by far the richest fossil herpetofauna known from the British Pleistocene. Caudates are represented by Triturus cristatus and T. vulgaris; anurans by Hyla sp., Bufo bufo, Rana arvalis, R. “esculenta” or R. ridibunda, and R. lessonae; testudines by Emys orbicularis; saurians by Anguis fragilis and Lacerta sp.; and snakes by Elaphe longissima, Natrix maura or N. tessellata, N. natrix, and Vipera berus. Of these 14 taxa, seven do not occur in Britain today, but are found in continental Europe. The fossil assemblage reflects the former connection of Britain to continental Europe and is consistent with a climate of milder winters and warmer summers than today during the later part of the Hoxnian Interglacial (Substage Ho IIIb).

There is disagreement about the time of the beginning of the Pleistocene. For instance, Repenning (1987), a North American, puts the beginning date at 1.9 million ybp. On the other hand, some modern Europeans studying the subject (e.g., Gibbard et al., 1991; Kolfschoten and Meulen, 1986; Roebroeks and Kolfschoten, 1995; Zagwijn, 1985, 1992) consider the epoch to have begun about 2.3 million ybp. The system used here, however, follows Sanchiz (in press), who accepts the official usage of Harland et al. (1990), who put the beginning of the Pleistocene at 1.64 million ybp. Evidence that the Pleistocene ended about 10,000 ybp (Meltzer and Mead, 1983) is widely accepted. This ending date correlates very closely with the terminal extinction of many large land mammal species. The Pleistocene is characterized by climatic oscillations and a series of glacial and interglacial events where great continental ice sheets advanced and retreated many times. The ice sheets were massive forces, sculpting the topography of the land and carrying much sedimentary material, including huge boulders and even megablocks of land up to 4 km in diameter, as far as 250 km in the Canadian prairies (MacStalker, 1977). In Britain and Europe, as well as in North America, the advance and retreat of ice sheets had a marked effect on the distribution of plant and animal life. Huge tracts of habitat were alternately obliterated and reopened several times, but other effects perhaps arc not so well known. For instance, during glacial times, so much atmospheric water was tied up in the formation of the ice that sea levels worldwide lowered markedly. On the other hand, sea levels rose during interglacial times when water was melting off the ice sheets. The most interesting and controversial biological event that took place in the Pleistocene was the sudden, almost worldwide, extinction of large land mammals, and to a lesser extent birds, that took place by the end of the epoch 10,000 years ago. At least 200 mammalian genera became extinct, among them large herbivores, the carnivores that preyed on them, and the scavengers that fed on the remains of both groups.

Localities in countries in the Geographic Divisions below arc numbered to correspond with those in the taxonomic accounts in Chapter 4. Figure 40 is an artists concept of some Pleistocene herpetological species and extinct mammals at the Shropham Pit Locality (Interglacial Component), Norfolk, England (Britain: Upper Pleistocene Site 10). Countries are arranged in divisions from west to cast, and from north to south when possible. Oceanic islands are listed under the country to which they belong. Malta is included with Italy because of its important Pleistocene herpetofauna and proximity to Sicily and Italy…. I. Northwest Division: Ireland and Britain, p. 130 II. French Division: France and Monaco, p. 142 III. Southwest Division: Spain, p. 149 IV. Northcentral Division: Netherlands, Belgium, Luxembourg, Germany, Austria, and Switzerland, p. 157 V. Northeast Division: Poland and the Czech Republic, p. 175 VI. Southeast Division: Italy, Hungary, Yugoslavia: (Croatia, Bosnia, Serbia), and Greece, p. 182… Pleistocene herpetofaunal records in Ireland are rare and consist mainly of records of Rana temporaria. More work needs to be done in this critical area for the study of the fragmentation of ranges of herpetological species in the Pleistocene.

In both Europe and North America, modern herpetological families and genera became established quite early in the Cenozoic, and modern species occurred as early as the Miocene. Because of deteriorating climates that began late in the Eocene, a marked decrease in herpetological diversity occurred in the Oligocene in both continents. However, both areas became herpetologically enriched in the Miocene. In post-Miocene times Europe was isolated from Africa and warm areas in the east by the Mediterranean Sea and eastern mountain ranges, and a depauperate herpetofauna developed there that continued into recent times. In North America, however, with its vast, accessible southern land mass, the richness of the Miocene herpetofauna (with the exception of several archaic colubrid genera [Parmley and Holman, 1995] that became extinct in the the Miocene) persisted into modern times. The following discussion of changes in the European herpetofauna in the Cenozoic era has been synthesized from Auge (1986), Ballón (1991a), Bailon ct al. (1988), Barbadillo et al. (1997), Crochet et al. (1981), Estes (1981, 1982, 1983), Fritz (1995), Holman (1995c), Milncr (1986), Milner et al. (1982), Mlynarski (1976), Rage (1984a, 1984c, 1986, 1993), Rage and Auge (1993), Rage and Ford (1980), Roček (1994), Sanchiz. (1977b, in press), Sanchiz and Mlynarski (1979), Sanchiz and Roček (1996), Spinar (1972), Szyndlar (1984, 1991b, 1991c), and Szyndlar and Bohme (1993). Because of the high probability that herpetological fossils have been identified correctly at the family level, herpetological families arc used here to reflect the taxonomic diversity of the European herpetofauna from the Paleocene through the Pliocene. In a following section, the earliest appearance of herpetological genera and species in the European Tertiary arc discussed. Extinct families are prefixed with an asterisk (*). Families that became extinct in Europe in the Cenozoic but presently occur elsewhere are prefixed with a number sign (#). Two primitive, extinct, presumably permanently aquatic salamander families, me *Albanerpetontidae and *Batrachosauroididae (the latter also known from the Tertiary of North America) made limited appearances in the Cenozoic of Europe. The *Albanerpetontidae occurred only in the Middle Miocene (having reappeared from the Cretaceous), and the *Batrachosauroididae occurred from the Upper Paleocene to the Lower Eocene.

As we have seen in Chapter 4, many invalid European Pleistocene amphibian and reptile species were named on the basis of insufficient and inadequately described fossils (e.g., Estes, 1981, 1983; Rage, 1984c; Sanchiz, in press). Some of these forms have been synonymized with modern species, but others are in taxonomic limbo because of the international rules of zoological nomenclature. We now turn to a consideration of the few European Pleistocene fossil herpetological species that have been recognized as valid in recent years. These taxa fit into three catagories: (1) an extinct Pliocene anuran taxon that extended into the Pleistocene, (2) large Lacerta species that lived on oceanic islands, and (3) Pleistocene species that are probably morphological variants of living forms. All of the following taxa are addressed in Chapter 4. No extinct species of Pleistocene salamanders are currently recognized in Britain or Europe. The genus * Pliobatrachus from the Pliocene of eastern Europe extended into the Lower Pleistocene of Poland and the Middle Pleistocene of Germany in the form of * Pliobatrachus cf. Pliobatrachus langhae. The *Palaeobatrachidae, the only family in the history of the Anura that became totally extinct (Roček, 1995), represents the only extinct herpetological family known in the Pleistocene of Britain and Europe, and *Pliobalrachus represents the only extinct herpetologcal genus known in the Pleistocene of the region. Rocck (1995) suggested that the *Palaeobatrachidae did not survive the Pleistocene cooling because of their prevailingly aquatic mode of life, unlike, for instance, the Ranidac and Bufonidae that were able to withdraw from iceobliterated areas and return when climatic conditions improved. *Lacerta goliath is a Pleistocene or Holocene species that is known only from two localities in the Canary islands (see Chapters 4 and 5). It is twice the size of Lacerta lepida, the largest modern European Lacerta. *Lacerta maxima is another very large Pleistocene or Holocene Lacerta that is endemic to the Canary Islands. This species is known from a single fossil locality (see Chapters 4 and 5) and is differentiated from * Lacerta goliath on the basis of several trenchant osteological characters.

In Chapter 5 we have seen that Pleistocene herpetofaunas are often used to suggest paleoenvironmental conditions. The present chapter discusses the validity of this use. With the exception of behavioral responses (and a few quasi-physiological adaptations in reptiles), herpetological species are poorly adapted to resist temperature changes. Or, to put it another way, amphibians and reptiles lack the complex internal physiological mechanisms that interact to regulate temperature in endotherms. This has led to the assumption by many that herpetological species, because of their supposed greater sensitivity to temperature changes, arc much better indicators of local thermal conditions than are birds and mammals. Moreover, most Quaternary amphibians and reptiles represent extant species whose ecological tolerances and habitat preferences are well known, whereas many Pleistocene endotherms, especially large mammals, are extinct species whose ecological traits and specific habitat requirements are not totally understood. This suggests that Pleistocene herpetofaunas should give more refined information about specific habitats than endothermic faunas. Also, it can be argued that most amphibian and reptile species are more spatially confined than endothermic ones (especially birds and large mammals) and that Pleistocene herpetological species indicate paleoenvironmental conditions of more restricted areas. Bailón and Rage (1992) address this subject in the light of their European experience: "They (amphibians and reptiles] arc unable to compensate for large climatic variations as endotherms (birds and mammals) can; therefore each amphibian and reptile species can live only in a definite climate." (p. 95). Moreover,… Amphibians and reptiles present another advantage: whereas endotherm vertebrates are represented in Quaternary fossiliferous localities by a not negligible percentage of extinct species, practically all fossil amphibians and reptiles of that age belong to extant species. If a species is extinct its ecological requirements cannot be known with certainty and arc open to speculation whereas living species present in fossiliferous assemblages afford accurate information, (p. 95)… They also state that the size of reptile home ranges is small, and that as these species are not the preferred prey of predaccous birds, they are probably not an admixture of species that live in a wide area around the locality. Let us examine these assumptions.

Compared to herpetological population adjustment patterns in North America (sec Holman, 1995c), the patterns in Britain and central and northern Europe seem to be rather straightforward. Basically, (1) very few herpetological species were present in ice-free areas during full glacial times, and (2) formerly glaciated areas were reinvaded by species from the south during warming cycles. Moreover, during climatic optimal warm times, several southern species existed well north of their present ranges. The invasion of southern Europe by northern populations in cold times is taken for granted (e.g., Rocek, 1995), although, as addressed in this chapter, it is difficult to document this in the fossil record. As indicated by geological and fossil evidence, the British Islands were connected to continental Europe during much of the Pleistocene. Although sea level changes in the British late Pleistocene arc a subject of some controversy (Stuart, 1982), it is generally agreed that Britain first separated from Ireland and then from the continent early in the Holocene. The classic idea is that the very depauperate British heretofauna of the cold part of the Devensian (last glacial stage) became somewhat, but not fully enriched by herpetological species during a warming trend that began about 10,000 ybp and lasted until about 8,500 ybp. The fact that Ireland has a much poorer modern herpetofauna (Triturus vulgaris, the rare Bufo calamita, Rana temporaria, and Lacerta vivipara) than Britain, which has six native species of amphibians and six native species of reptiles (Fra/,er, 1983; Smith, 1964), is attributed to Ireland's early separation from Britain. The Irish herpetofauna suggests that this separation occurred rather soon after the final withdrawal of the Devensian (last glacial) ice sheet. One of the most common questions asked about snakes, especially near St. Patrick's Day, is, "Have there ever been any snakes in Ireland?" No fossil snakes have ever been found in Ireland. But since Ireland lacks a terrestrial fossil record during most of the time that snakes have existed, it would seem that snakes could have lived in Ireland during some part of geological time. As far as I am aware, the few Pleistocene deposits containing herpetological remains in Ireland represent very late Devensian (last glacial) times.

This chapter consists of annotated taxonomic accounts of Pleistocene amphibians and reptiles recorded from the study area (see Fig. 1). General external characters, habits, and distributional patterns of modern taxa of amphibians and reptiles that occur in the British and European Pleistocene in this and following chapters are from the author's unpublished field notes and photographs as well as the following sources: Arnold and Burton (1978), Ballasina (1984), Beebee (1983), Berger et al. (1969), Duellman (1993), Duellman and Trueb (1986), Engelmann et al. (1986), Ernst and Barbour (1989), Escriva (1987), Estes (1981, 1983), Frazer (1983), Frost (1985), Gunther (1996), Halliday and Adler (1986), Hellmich (1962), Hvass (1972), King and Burke (1989), Matz (1983), Noble (1931), Smith (1964), Sparreboom (1981), and Zug (1993). The reader is cautioned not to attempt to identify Pleistocene amphibian and reptile fossils solely on the basis of skeletal characters discussed or skeletal figures presented in this book—or in other publications. To identify Pleistocene amphibian and reptile fossils accurately, it is necessary to compare them with adequate modern and fossil skeletal material. Pleistocene locality numbers below correspond with locality numbers in Chapter 5. Pleistocene caudate amphibians are usually identified on the basis of individual trunk vertebrae (see Holman, 1995c, p. 83). Figure 3 illustrates the important features of a trunk vertebra of Triturus cristatus from the Middle Pleistocene of Cudmore Grove, Essex, England.

The Pleistocene epoch or Ice Age, an extended period of advancing and retreating ice sheets, is characterized by striking climatic oscillations and sea level fluctuations. This age saw the rise and spread of humans and a great extinction of large mammals by the end of the epoch; in fact, the world today is essentially the product of dramatic changes that took place in the Pleistocene. This book, a companion to the author's Pleistocene Amphibians and Reptiles in North America, discusses the Pleistocene amphibians and reptiles in Britain and the European continent eastward through present-day Poland, the Czech Republic, Hungary, the Yugoslavian republics, and Greece. The book begins with a general discussion of the Pleistocene in Britain and Europe with an emphasis on regional terms used to define Pleistocene chronological events. Next, a look at the pre-Pleistocene herpetofauna of the study area sets the stage for a discussion of Pleistocene herpetofauna. A significant section of the book consists of a "bestiary," a series of annotated taxonomic accounts of Pleistocene herpetological taxa from the region. Following this is the interpretive section, beginning with a discussion of herpetological species as paleoenvironmental indicators and continuing with an analysis of herpetological population adjustments to Pleistocene events in Britain and Europe, and then with a discussion of extinction patterns in the region. Finally, the author compares Pleistocene herpetological events in Europe with those in North America. This volume and its companion together provide an up-to-date and comprehensive review of Pleistocene herpetofaunas across a significant portion of the Northern Hemisphere.

A general introduction to the Pleistocene with an emphasis on herpetological remains was presented in the companion volume Pleistocene Amphibians and Reptiles in North America (Holman, 1995c). For a general introduction to the Pleistocene that gives much attention to Britain and Europe, the reader is referred to Sutcliffe (1985). A detailed account of Pleistocene mammals in Britain is given by Stuart (1982), and a general account of Pleistocene mammals in Europe is given by Kurten (1968). The present chapter deals mainly with chronological divisions of the Pleistocene in Britain and Europe. Early geologists recognized that glacial deposits and land forms existed far south of existing glaciated areas, and they correctly reasoned that these features indicated not only the presence of ice sheets but the onset of cold climates, as well. As these features were mapped and stratigraphic studies were made, it was found that some sections contained weathered zones of organic soils and plant remains between layers of glacially derived sediments. It was suggested that these organic zones represented nonglacial environments and that ice sheets must have advanced and retreated several times. In Europe, before studies of deep sea sediments were made, Pleistocene chronological events were determined on the basis of piecemeal evidence from terrestrial sediments. The earliest widely accepted chronology of climatic Pleistocene intervals was the classic fourfold subdivision of Pleistocene glacial events in the Alps by Penck and Bruckner (1909). These glacial stage names, from oldest to youngest, are Gu'nz glacial, Mindcl glacial, Riss glacial, and Wiirm glacial. Between the glacial stages, intcrglacial stages were designated by compound names based on the underlying and overlying glacial stages (e.g., The Gunz-Mindel intcrglacial stage lies between the Giinz and Mindel glacial stages). These Alpine glacial stages have been widely used, and one still finds references to them (especially the younger stages) in the recent literature (e.g., Fritz, 1995).

A new species, Emydoidea hutchisoni, of the heretofore monotypic genus Emydoidea is described from the Late Barstovian Land Mammal Age (Medial Miocene) of the West Valentine Quarry (University of Nebraska State Museum Locality Cr 114), Cherry County, north-central Nebraska. The fossil species differs from the modern one in having a smaller, thicker, less kinetic shell and in other details of individual shell bones. The transition from Emydoidea hutchisoni to the modern species Emydoidea blandingii took place sometime between the Late Barstovian (Medial Miocene) and the Late Hemphillian (Late Miocene). An evolutionary tendency in Emydoidea appears to have been an increase in the size of the shell, a thinning of the shell, and an increase in plastral kinesis. Emydoidea is a unique genus of North Amer- ican turtle with a flattened head, bulging eyes, terminally notched upper jaw, very long neck, and a gape and suck method of feeding. A mov- able plastral hinge occurs in the sole modern species, Emydoidea blandingii, that today is found in wetlands, mainly in states bordering the Great Lakes. The modern species has also been found in the latest Miocene (Late Hemphillian), Plio- cene and Pleistocene deposits. Bramble (1974) showed that the genera Emys (European pond tortoises), Emydoidea (Bland- ing's turtles), and Terrapene (American box tur- tles) form a singular morphocline, in which each genus developed a progressively more complex mechanism to close the shell. He united these forms as the Emys Group. In this group, Emys is the least derived in the shell-closing mecha- nism and Terrapene is the most derived. Hutchison (1981) reported the earliest fossil occurrence of the genus Emydoidea when he re- corded Emydoidea sp. from the Late Barstovian (Medial Miocene) Railroad Quarry (University

At least four species of anurans, one tortoise and one snake were identified from the Ipswichian interglacial bed (Late Pleistocene) of the Itteringham Gravel Pit, Norfolk, England. A tree frog (Hyla sp.) is reported for the first time as a British fossil. The herpetofauna indicates that the major habitat was a lentic one. The occurrence of the tree frog (Hyla sp.), continental water frogs (Rana), and the European pond tortoise (Emys orbicularis) indicates a continental climate with warmer summers than occur in England today. The mammalian fauna of the British Pleistocene has been well-studied (Stuart, 1982), but the British Pleistocene herpetofauna has been largely neglected until recently. These recent works include reports of the European pond tortoise from interglacial sites (Stuart, 1979, 1982), and short herpetofaunal papers on Cromerian (Holman, 1987c; Holman et al., 1988), Hoxnian (Holman, 1987a), Ipswichian (Holman, 1987b), Devensian/Flandrian (Holman, 1988) and Flandrian (Holman, 1985, 1987a) localities. Studies of fossil herpetofaunas are important in making paleoecological interpretations, for modern amphibians and reptiles have specific ecological requirements and most Pleistocene species have modern equivalents that have been well-studied in Britain and on the continent. Moreover, certain species may be particularly important in indicating specific environmental conditions because of stringent climatic reproductive constraints (Stuart, 1979). The Ipswichian Interglacial Stage.-Except for the Flandrian, the Ipswichian is the best known of the British interglacials. The Ipswichian (ca. 120,000-110,000 years before present) occurs between the cold glacial times of the older Wolstonian stage and the younger Devensian stage. Stuart (1982) provides a general discussion of the most important Ipswichian sites and their vertebrate fauna. The presence of fossils of the African hippo (Hippopotamus amphibius) is generally accepted as diagnostic of the Ipswichian. Some other mammals which no longer are native to Britain but do appear in the Ipswichian are the horse (Equus ferus), spotted hyena (Crocuta crocuta) and the lion (Panthera leo). The Ipswichian has also yielded the European pond tortoise (Emys orbicularis) from many of its sites. The type site of the Ipswichian is Bobbitshole, Ipswich, England. The Itteringham Deposit.-The Itteringham Gravel Pit (National Grid Reference 139305) is located beside the River Bure in the parish of Oulton, 6 km west of Aylsham, Norfolk, England. Deposits belonging to four distinct climatic stages have been identified. The uppermost valley deposits (mostly peat) belong to the present (Flandrian) interglacial. Beneath these are gravels and clays with fossil and sedimentary indications of intense cold and these are assigned to the last (Devensian) glacial. Stratigraphically lower are detrital muds and organic sands which are fully interglacial in character. 33 This content downloaded from 207.46.13.167 on Thu, 21 Jul 2016 05:09:32 UTC All use subject to http://about.jstor.org/terms L. A. HALLOCK ET AL.