See also:Sir C .
See also:Lyell in 1833 for the
See also:lower subdivision of the rocks of the
See also:Tertiary Era . The
See also:term was intended to convey the idea that this was the
See also:period which saw the
See also:dawn of the
See also:recent or existing forms of
See also:life, because it was estimated that among the fossils of this period only 32 % of the
See also:species are still living . Since Lyell's
See also:time much has been learned about the
See also:fauna and
See also:flora of the period; and many palaeontologists doubt if any of the Eocene species are still extant, unless it be some of the lowest forms of life . Nevertheless the name is a convenient one and is in general use . The Eocene as originally defined was not long
See also:left intact, for E . Beyrich in 1854 proposed the term " Oligocene " for the upper portion, and later, in 1874, K . Schirnper suggested " Paleocene " as a
See also:separate appellation for the lower portion . The Oligocene division has been generally accepted as a distinct period, but " Paleocene " is not so widely used . In
See also:Europe the close of the Cretaceous period was marked by an extensive emergence of the
See also:land, accompanied, in many places, by considerable erosion of the Mesozoic rocks; a prolonged
See also:interval elapsed before a relative depression of the land set in and the first Eocene deposits were formed . The early Eocene formations of the
See also:basin were of fresh-
See also:water and brackish origin; towards the
See also:middle of the period they had become marine, while later they reverted to the
See also:original type . In
See also:southern and eastern Europe changes of
See also:sea-level were less pronounced in character; here the
See also:late Cretaceous seas were followed without much modification by those of the Eocene period, so
See also:rich in foraminiferal life .
In many other regions, the
See also:gap which separates the Tertiary from the Mesozoic rocks in the neighbourhood of London and Paris does not exist, and the boundary
See also:line is difficult to draw . Eocene strata succeed Cretaceous rocks without serious unconformity in the Libyan
See also:area, parts of Denmark, S.E .
See also:Alps, India, New Zealand and central N .
See also:America . The unconformity is marked in England, parts of
See also:Egypt, on the
See also:Atlantic coastal plain and in the eastern gulf region of N . America, as well as in the marine Eocene of western
See also:Oregon . The clastic
See also:Flysch formation of the Carpathians and
See also:northern Alps appears to be of Eocene age in the upper and Cretaceous in the lower
See also:part . The Eocene sea covered at various times a
See also:strip of the Atlantic
See also:coast from New Jersey southward and sent a great
See also:tongue or
See also:bay up the
See also:Mississippi valley; similar epicontinental seas spread over parts of the Pacific border, but the plains of the interior with the mountains on the west were meanwhile being filled with terrestrial and lacustrine deposits which attained an enormous development . This great extension of non-marine formations in the Eocene of different countries has introduced difficulties in the way of exact correlation; it is safer, therefore, in the
See also:present state of know-ledge, to make no attempt to find in the Eocene strata of America and India, &c., the precise
See also:equivalent of subdivisions that have been determined with more or less exactitude in the London-Paris-Belgian area . It is possible that in Eocene times there existed a greater continuity of the northern land masses than obtains to-
See also:day . Europe at that time was probably
See also:united with N . America through
See also:Iceland and
See also:Greenland; while on the other side, America may have joined
See also:Asia by the way of
See also:Alaska .
On the other
See also:hand, the great central, mediterranean sea which stretched across the
See also:Eurasian continents sent an
See also:arm northward somewhere just east of the Ural mountains, and thus divided the northern land mass in that region . S . America,
See also:Australia and perhaps Africa may have been connected more or less directly with the
See also:Antarctic continent . Associated, no doubt, with the crustal movements which closed the Cretaceous and inaugurated the Eocene period, there were
See also:local and intermittent manifestations of volcanic activity throughout the period . Diabases, gabbros, serpentines, soda-potash granites, &c., are found in the Eocene of the central and northern Apennines . Tuffs occur in the Veronese and Vicentin Alps—Ronca and Spelecco
See also:schists . Tuffs, basalts and other igneous rocks appear also in
See also:Wyoming, California, Oregon,
See also:Colorado; also') in Central America, the Antillean region and S . America . It has been very generally assumed by geologists, mainly upon the evidence of plant remains, that the Eocene period opened with a temperate
See also:climate in northern latitudes; later, as indicated by the London
See also:Alum Bay and
See also:Bournemouth beds, &c., the temperature appears to have been at least subtropical . But it should be observed that the frequent admixture of temperate forms with what are now tropical species makes it difficult to speak with certainty as to the degree of warmth experienced . The occurrence of lignites in the Eocene of the Paris basin,
See also:Tirol and N . America is worthy of
See also:consideration in this connexion .
On the other hand, the coarse
See also:boulder beds in the lower Flysch have been regarded as evidence of local glaciation; this would not be inconsistent with a period of widespread geniality of climate, as is indicated by the large
See also:size of the nummulites and the dispersion of the marine MolIusca, but the evidence for glaciation is not yet conclusive . Eocene Stratigraphy.—InBritain, with the exception of the Bovey beds (q.v.) and the
See also:leaf-bearing beds of
See also:Antrim and
See also:Mull, Eocene rocks are confined to the south-eastern portion of England . They lie in the two well-marked synclinal basins of London and Hampshire which are conterminous in the western area (Hampshire,
See also:Berkshire), but are separated towards the east by the denuded anticline of the
See also:Weald . The strata in these two basins have been grouped in the following manner: . London Basin . Hampshire Basin . Upper Upper Bagshot Sands . Headon
See also:Hill and
See also:Barton Sands . Middle Bagshot Beds and Bracklesham Beds and leaf Middle - part of Lower Bagshot beds of Bournemouth and 1 . Beds . Alum Bay . 'Part of Lower Bagshot Beds, London Clay,
See also:Blackheath and Old-haven Beds,
See also:Woolwich and ReadingBeds,
See also:Thanet Sands .
The Thanet sands have not been recognized in the Hampshire basin; they are usually
See also:pale yellow and greenish sands 'with streaks of clay and at the
See also:base; resting on an evenly denuded
See also:surface of
See also:chalk is a very
See also:constant layer of
See also:green-coated, well-rounded chalk
See also:flint pebbles . It is a marine formation, but fossils are scarce except in E . Kent, where it attains its most
See also:complete development . The Woolwich and
See also:Reading beds (see READING BEDS) contain both marine and estuarine fossils . In western Kent, between the Woolwich beds and the London Clay are the Oldhaven beds or Blackheath pebbles, 20 to 40 ft., made up almost entirely of well-rounded flint pebbles set in sand; the fossils are marine and estuarine . The London Clay, 500 ft. thick, is a marine deposit consisting of blue or
See also:brown clay with sandy layers and septarian nodules; its equivalent in the Hampshire area is sometimes called the
See also:Bognor Clay, well exposed on the coast of
See also:Sussex . The Bagshot, Bracklesham and Barton beds will be found briefly described under those heads .
See also:Crossing the
See also:English Channel, we find in northern France and Belgium a series of deposits identified in their general characters with those of England . The anticlinal
See also:ridge of the English Weald is prolonged south-eastwards on to the continent, and separates the Belgian from the French Eocene areas much as it separates the areas of London and Hampshire; and it is clear that at the time of deposition all four regions were intimately related and subject to similar variations of marine and estuarine conditions . With a series of strata so variable from point to point it is natural that many purely local phases should have received distinctive names; in the Upper Eocene of the Paris basin the more important formations are the highly fossiliferous marine sands known as the " Sands of Beauchamp " and the local fresh-water
See also:limestone, the "Calcaire de St Ouen." The Middle Eocene is represented by the well-known Calcaire grossier," about qo ft. thick . The beds in this series vary a
See also:deal lithologically, some being sandy, others marly or glauconitic; fossils are abundant . The Upper Calcaire grossier or " Caillasses " is a fresh-water formation; the middle division is marine; while the lower one is partly marine, partly of fresh-water origin .
The numerous quarries and mines for
See also:stone in the neighbourhood of Paris have made it possible to acquire a very precise knowledge of this division, and many of the beds have received
See also:trade names, such as " Rochette," "
See also:Roche," " Banc
See also:franc," " Banc vert," " Cliquart," "
See also:Saint Nom;" the two last named are dolomitic . Below these limestones are the nummulitic sands of Cuise and
See also:Soissons . The Lower Eocene contains the lignitic plastic clay (argile plaslique) of Soissons and elsewhere; the limestones of Rilly and Sezanne and the greenish glauconitic sands of Bracheux . The relative position of the above formations with respect to those of Belgium and England will be seen from the table of Eocene strata . The Eocene deposits of southern Europe differ in a marked manner from those of the Anglo-Parisian basin . The most important feature is the great development of nummulitic limestone with thin marls and nummulitic sandstones . The sea in which the nummulitic limestones were formed occupied the site of an enlarged Mediterranean communicating with similar
See also:waters right
See also:round the
See also:world, for these rocks are found not only in southern Europe, including all the Alpine tracts,
See also:Greece and
See also:Turkey and southern Russia, but they are well
See also:developed in northern Africa, Asia Minor,
See also:Palestine, and they may be followed through
See also:Baluchistan, India, into
See also:Borneo and the Philippines . The nummulitic limestones are frequently hard and crystalline, especially where they have been subjected to
See also:elevation and
See also:compression as in the Alpine region, Io,000 ft. above the sea, or from 16,000, to 20,000 ft., in the central Asian
See also:plateau . Besides being a wide-spread formation the nummulitic limestone is locally several thousand feet thick . While the foraminiferal limestones were being formed over most of southern Europe, a series of clastic beds were in course of formation in the Carpathians and the northern Alpine region, viz. the Flysch and the Vienna
See also:sandstone . Some portions of this Alpine Eocene are coarsely conglomeratic, and in places there are boulders of Areas in which Middie Eocene Roche we found Non-marine Eocene deposits of N.Amerioa Eocene Rocks absent or unknown —Suggested limits oftand de
See also:Sect about
See also:Mid . Eocene time Distribution of Eocene Rocks (Mid .
See also:star de Lapq,ent Lower London Clay and the equivalent Bognor Beds, Woolwich and Reading Beds . non-local rocks of enormous dimensions included in the argillaceous or sandy
See also:matrix . The occurrence of these large boulders together with the scarceness of fossils has suggested a glacial origin for the formation; but the evidence hitherto collected is not conclusive . C . W. von Gumbel has classified the Eocene of the northern Alps (
See also:Bavaria, &c.) as follows: Upper Eocene Flysch and Vienna sandstone, with younger num- mulitic beds and Haring
See also:group . Middle „ Kressenberg Beds, with older nummulitic beds . Lower Burberg Beds, Greensands with small nummulites . The Haring group of northern Tirol contains
See also:lignite beds of some importance: In the southern and S.E . Alps the following divisions are recognized . Upper Eocene Macigno or Tassello—Vienna Sandstone, conglomerates, marls and shales . Middle „ Nummulitic limestones, three subdivisions . Liburnian stage (or Proteocene), foraminiferal limestones with fresh-water intercalations at the top and bottom, the Cosina beds, fresh-water in the middle of the series .
In the central and northern Apennines the Eocene strata have been subdivided by Prof . F . Sacco into an upper Bartonian, a middle Parisian and a lower Suessonian series . In the middle member are the representatives of the Flysch and the Macigno . These Eocene strata are upwards of 5500 ft. thick . In northern Africa the nummulitic limestones and sandstones are widely spread; the lower portions comprise the Libyan group and the shales of Esneh on theNile (Flandrien), the Alveolina beds of Sokotra and others; the Mokattam stage of Egypt is a representative of the later Eocene . Much of the N .
See also:African Eocene contains phosphatic beds . In India strata of Eocene age are extensively developed ; in
See also:Sind the marine Ranikot beds, 1500 to 2000 ft., consisting of
See also:clays with
See also:gypsum and lignite, shales and sandstones; these beds have, side by side with Eocene nummulites, a few fossils of Cretaceous
See also:affinities . Above the Ranikot beds are the massive nummulitic limestones and sand-stones of the Kirthar group; these are succeeded by the nummulitic limestones and shales at the base of the Nari group . In the southern Himalayan region the nummulitic phase of Eocene deposit is well developed, but there are difficulties in fixing the line of demarcation between this and the younger formations . The lower part of the Sirmur series of the
See also:district may belong to this period ; it is subdivided into the Kasauli group and the Dagshai group with the Subathu group at the base .
Beneath the thick nummulitic Eocene limestone of the
See also:Salt Range are shales and marls with a few
See also:coal seams . The marine Eocene rocks of N . America are most extensively developed round the coast of the Gulf of Mexico, whence they spread into the valley of the Mississippi and, as a comparatively narrow strip, along the Atlantic coastal plain to New Jersey . The series in
See also:Alabama, which may be taken as typical of the Gulf coast Eocene, is as follows: Upper Jacksonian,
See also:White limestone of Alabama (and
See also:Vicksburg?) . Middle Claibornian Claiborne series . Buhrstone series . Lower Chickasawan Sands and lignites . Midwayan or
See also:Clayton formation, limestones . The above succession is not fully represented in the Atlantic coast states . On the Pacific coast marine formations are found in California and Oregon; such are the Tejon series with lignite and oil; the Escondido series of S . California (7000 ft.), part of the Pascadero series of the
See also:Santa Cruz Mountains; the
See also:Pulaski, Tyee, Arago and Coaledo beds—with coals—in Oregon . In the
See also:Puget formation of Washington we have a great series of sediments, largely of brackish water origin, and in parts coal-bearing .
See also:total thickness of this formation has been estimated at 20,000 ft . (it may prove to be less than this), but it is probable that only the lower portion is of Eocene age . The most interesting of the N .
See also:American Eocene deposits are those of the Rocky Mountains and the adjacent western plains, in Wyoming,
See also:Nebraska, Colorado, &c.; they are of terrestrial, lacustrine or aeolian origin, and on this account and because they were not strictly synchronous, there is considerable difficulty in placing them in their true position in the time-scale . The
See also:main divisions or groups are generally recognized as follows: Mammalian Zonal Forms . Diplacodon . l Telmatotherium . Middle 2 Bridger Group, 2000 ft . ( ? = Clai- bornian) . . . . Uintatherium .
See also:River Group, 800 ft . Bathyopsis . Lower " Wasatch Group, 2000 ft . ( ? = Chicka- sawan) Coryphodon . Basal i 5 Torrejon Group, 300 ft . Pantolambda . Puerco Group, 500 to 1000 ft . . Polymastodon . ' South of the Uinta Mts. in
See also:Utah . 2 Fort Bridger Basin . 2 Wind river in Wyoming .
" Wasatch Mts. in Utah . Torrejon in New Mexico . 6 Puerco river New Mexico.663 The FortUnion beds of
See also:Canada and parts of Montana and N . Dakota are probably the
See also:oldest Eocene strata of the Western Interior; they are some 2000 ft. thick and possibly are equivalent to the Midwayan group . But in these beds, as in those known as Arapahoe, Livingston,
See also:Ohio and
See also:Ruby, which are now often classed as belonging to the upper
See also:Laramie formation, it is safer to regard them as a transitional series between the Mesozoic and Tertiary systems . There is, however, a marked unconformity between the Eocene Telluride or
See also:Miguel and
See also:Canyon formations of Colorado and the underlying Laramie rocks . Many local aspects of Eocene rocks have received
See also:special names, but too little is known about them to enable them to be correctly placed in the Eocene series . Such are the Clarno formation (late Eocene) of the
See also:John Day basin, Oregon, the Pinyon
See also:conglomerate of Yellowstone
See also:Park, the Sphinx conglomerate of Montana, the Whitetail conglomerate of
See also:Arizona, the Manti shales of Utah, the Mojave formation of S . California and the Amyzon formation of Nevada . Of the Eocene of other countries little is known in detail . Strata of this age occur in Central and S . America (
See also:Patagonia-Megellanian series—Brazil, Chile,
See also:Argentina), in S .
Australia (and in the Great AustralianBight), New Zealand, in Seymour
See also:Island near
See also:Graham Land in the Antarctic Regions, Japan,
See also:Java, Borneo, New
See also:Moluccas, Philippines, New
See also:Caledonia, also in Greenland, Bear Island, Spitzbergen and
See also:Siberia . Organic Life of the Eocene Period.—As it has been observed above, the name Eocene was given to this period on the ground that in its fauna only a small percentage of living species were present; this estimation was founded upon the assemblage of invertebrate remains in which, from the commencement of this period until the present day, there has been comparatively little
See also:change . The real biological
See also:interest of the period centres around the higher vertebrate types . In the marine
See also:mollusca the most noteworthy change is the entire
See also:absence of ammonoids, the group which throughout the Mesozoic era had taken so prominent a place, but disappeared completely with the close of the Cretaceous . Nautiloids were more abundant than they are at present, but as a whole the Cephalopods took a more subordinate part than they had done in previous periods . On the other hand, Gasteropods and Pelecypods found in the numerous shallow seas a very suitable environment and flourished exceedingly, and their shells are often preserved in a state of great perfection and in enormous numbers . Of the Gasteropod genera Cerithium with its estuarine and lagoonal forms Potamides, Potamidopsis, &c., is very characteristic; Rostellaria, Voluta, Fusus, Pleurotoma, Conus, Typhis, may also be cited . Cardium, Venericardia, Crassatella, Corbulomya, Cytherea,
See also:Lucina, Anomia, Ostrea are a few of the many Pelecypod genera . Echinoderms were represented by abundant sea-urchins, Echinolampas, Linthia, Conoclypeus, &c . Corals flourished on the numerous reefs and approximated to
See also:modern forms (Trochosmilia, Dendrophyllia) . But by far the most abundant marine organisms were the
See also:foraminifera which flourished in the warm seas in countless myriads . Foremost among these are the Nummulites, which by their extraordinary numerical development and great size, as well as by their wide distribution, demand special recognition .
Many other genera of almost equal importance as
See also:rock builders, lived at the same time: Orthophragma, Operculina, Assilina, Orbitolites, Miliola, Alveolina . Crus' acea were fairly abundant (Xanthopsis,
See also:Portunus), and most of the Orders and many families of modern
See also:insects were represented . When we turn to the higher forms of life, the
See also:reptiles and mammals, we find a remarkable contrast between the fauna of the Eocene and those periods which preceded and succeeded it . The great group of Saurian reptiles, whose members had held dominion on land and sea during most of the Mesozoic time, had completely disappeared by the beginning of the Eocene; in their place placental mammals made their appearance and rapidly became the dominant group . Among the early Eocene mammals no trace can be found of the numerous and clearly-marked orders with which we are
See also:familiar to-day; instead we find obscurely differentiated forms, which cannot be fitted without violence into any of the modern orders . The early placental mammals were generalized types (with certain non'-placental characters) with potentialities for rapid divergence and development in the direction of the more specialized modern orders . Thus, the
See also:Creodonta foreshadowed the
See also:Carnivora, the Lower Upper 1 Uinta Group, 800 ft . ( ? = Jacksonian) . Stages . Paris Basin . England .
Belgian Basin . Mediterranean Flysch North America . regions and Phase . Great Central sea . Bartonien.' Limestone of Saint-Ouen . Barton beds . Uinta Group and Sands of Mortefontaine . Sands of Lede . Jacksonian . Sands of Beauchamp . Upper Bagshot sands . Sands of Auvers .
a a o - , Bracklesham and
See also:Bourne- Laekenien . Lutetien . Calcaire grossier. mouth beds . Bruxellien . a Bridger Group and Lower Bagshot sands . Paniselien . Claibornian . Ypresien . Nummulitic sands of Alum Bay leaf beds . Sands of
See also:Mons en d a Wind River Group . Wasatch Group Soissons and Sands of Pevele. o c and Cuise and Aizy .
See also:Flanders Clay. a a: a a a c E N a' London Clay .
m m Oldhaven beds . Upper Landenien a El' a [ Plastic Clay and lignite sands . El ~ Chickasawan . V a beds . Woolwich and Reading beds . o .b.c u7 Sands of Ostri- a a° , Limestones of Rilly and Thanet sands.
See also:court . E a. o Torrejon Group Sezanne . a ~- a and Z d Sands of Rill y and Bra- Landenien
See also:tuff- a . Midwayan . cheux . eau . a F Marls of Gelinden .
Puerco Group . Condylarthra presaged the herbivorous groups; but before the close of this period, so favourable were the conditions of life to a rapid
See also:evolution of types, that most of the great orders had been clearly defined, though none of the Eocene genera are still extant . Among the early carnivores were Arctocyon,Palaeonictis, Amblyclonus, Hyaenodon, Cynodon, Provivera, Patriofelis . The
See also:dog-like forms did not appear until late in the period, in Europe; and true
See also:cats did not arrive until later, though they were represented by Eusmilus in the Upper Eocene of France . The primitive ungulates (Condylarths) were generalized forms with five effective toes, exemplified in
See also:Phenacodus . The
See also:Amblypoda, with five-toed stumpy feet (Coryphodon), were prominent in the early Eocene; particularly striking forms were the Dinoceratidae, Dinoceras, with three pairs of horns or protuberances on its massive
See also:skull and a pair of huge canine teeth projecting downwards; Tinoceras, Ulntatherium, Loxophodon, &c.; these elephantine creatures, whose remains are so abundant in the Eocene deposits of western America, died out before the close of the period . The divergence of the hcofed mammals into the two prominent divisions, the
See also:odd-toed and even-toed, began in this period, but the former did not get beyond the three-toed stage . The least differentiated of the odd-toed group were the Lophiodonts: tapirs were foreshadowed by Systemodon and similar forms (
See also:Palaeotherium, Paloplotherium); the
See also:peccary-like Hyracotherium was a forerunner of the
See also:horse, Hyrochinus was a primitive
See also:rhinoceros . The evolution of the horse through such forms as Hyracotherium, Pachynolophus, Eohippus, &c., appears to have proceeded along parallel lines in Eurasia and America, but the true horse did not arrive until later . Ancestral
See also:deer were represented by Dichobune, Amphitragulus and others, while many small hog-like forms existed (Diplopus, Eohyus, Hyopotamus, Homacodon) . The primitive stock of the camel group developed in N . America in late Eocene time and sent branches into S .
America and Eurasia . The edentates were very generalized forms at this period (Gan- ' Bartonien from Barton, England . Lutetien „ Lutetia = Paris . Ypresien „
See also:Ypres, Flanders . Landenien „ Landen, Belgium . Thanetien „ The Isle of Thanet . Sparnacien „ Sparnacum =
See also:Epernay . Laekenien „ Laeken, Belgium . Bruxellien ., Brussels . Panisehen Mont Panieel, near Mons . Other names that have been applied to subdivisions of the Eocene not included in the table are Parisien and Suessonien (Soissons) ; Ludien (Ludes in the Paris basin) and Priabonien (Priabona in the Vicentine Alps) ; Heersien (Heer near
See also:Maastricht) and Wemmelien :Wemmel, Belgium); very many more might be mentioned,odonta); the rodents (
See also:Tillodontia) attained a large size for members of this group, e.g . Tillotherium .
The Insectivores had Eocene forerunners, and the Lemuroids—probable ancestors of the apes—were forms of great interest, Anaptomorphus; Microsyops, Heterohyus, Microchaerus, Coenopithecus; even the Cetaceans were well represented by Zeuglodon and others . The non-placental mammals although abundant were taking a secondary place; Didelphys, the primitiveopossum, is note-worthy on account of its wide
See also:geographical range . Among the birds, the large flightless forms, Eupterornis, Gastornis, were prominent, and many others were present, such as the ancestral forms of our modern gulls, albatrosses, herons, buzzards, eagles, owls, quails, plovers . Reptiles were poorly represented, with the exception of crocodilians, tortoises, turtles and some large
See also:snakes . The flora of the Eocene period, although full of interest, does not convey the impression of newness that is afforded by the fauna of the period . The reason for this difference is this: the newer flora had been introduced and had developed to a considerable extent in the Cretaceous period, and there is no
See also:sharp break between the flora of the earlier and that of the later period; in both we find a mixed assemblage—what we should now regard as tropical palms, growing side by side with mild-temperate trees . Early Eocene
See also:plants in N . Europe, oaks, willows, chestnuts (Castanea), laurels, indicate a more temperate climate than existed in Middle Eocene when in the Isle of
See also:Wight, Hampshire and the adjacent portions of the continent, palms,
See also:cinnamon flourished along with the
See also:cypress and ferns . The late Eocene flora of Europe was very similar to its descendant in modern
See also:Australasia . See A. de Lapparent, Traite de geologie, vol. iii . (5th ed., 1906), which contains a good general account of the period, with numerous references to original papers . Also R .
See also:Newton, Systematic,
See also:List of the
See also:Frederick E .
See also:Edwards Collection of
See also:British Oligocene and Eocene Mollusca in the British Museum (Natural
See also:History) (1891), pp . 299-325 G . D .
See also:Harris, " A Revision of our Lower Eocenes," Proc . Geologists' Assoc. x., 1887–1888; W . B .
See also:Clark, " Correlation Papers: Eocene " (1891), U.S . Geol . Survey Bull . No .
83 . For more recent literature consult
See also:Geological Literature added to the Geological Society's Library, published annually by the society . (J . A .
ENZYME (Gr. Eve uµos, leavened, from v, in, and Om...
CHARLES GENEVIEVE LOUISE AUGUSTE ANDRE TIMOTHEE EON...
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