Eocene Fossil Research Articles

Eocene fossil mammalia from the Sand Wash Basin, northwestern Moffat County, Colorado

Eocene fossil mammalia from the Sand Wash Basin, northwestern Moffat County, Colorado

Relation of Rocky Point Member (Peedee Formation) to Cretaceous-Tertiary Boundary in North Carolina

The Rocky Point Member of the Peedee Formation (Cretaceous of North Carolina), exposed in quarries near Castle Hayne and Rocky Point, was named informally by Swift and Heron and herein is designated formally as a stratigraphic unit. In the type section, it consists of 10.5 m of pelecypod biosparrudite, unconsolidated quartz arenite, and an alteration of the two. The invertebrate macrofauna and microfauna indicate a Maestrichtian (= Navarro) age. Confusion has arisen over the problem of real or supposed mechanical mixing of faunas between Upper Cretaceous units and the overlying Castle Hayne Formation of Eocene age. The Rocky Point Member is overlain with spectacular unconformity by a hard phosphate-pebble conglomerate which is the basal bed of the Castle Hayne Formation. This conglomerate has some reworked Cretaceous fossils together with Eocene fossils, as first indicated by Tuomey. The underlying Rocky Point Member has more resemblance to some Castle Hayne outcrops in North Carolina than it does to the typical glauconitic, argillaceous sands of the Peedee Formation. It is probably because of this fact that the idea of mechanical mixing of faunas, moderately true for the basal Castle Hayne conglomerate, has been extended inc rrectly to include the Rocky Point Member. The presence of unworn, delicate specimens of the echinoid, Hardouinia, and a spiny Exogyra mitigate against any notable amount of abrasion. This, coupled with the presence of exclusively Cretaceous foraminiferal species and the absence of any exclusively Eocene species, makes the mechanical-mixing theory inapplicable to the Rocky Point Member. The Cretaceous-Tertiary boundary is the conspicuous unconformity between the Castle Hayne Formation and the Rocky Point Member of the Peedee Formation in southeastern North Carolina.

Geologic Setting of an Eocene Fossil Deposit on Eua Island, Tonga

The geology of a very important upper Eocene fossil deposit is described, together with geology of the island not previously recorded. A dike complex indicates that the lavas were erupted chiefly through narrow dikes. Pillow lavas are scarce. Three series of tuffs or tuffaceous sediments and limestone of three distinctly different ages occur. The limestones are upper Eocene, Miocene, and Pliocene-Pleistocene in age. The island history has been one of volcanism, uplift, faulting, marine and stream erosion, and limestone deposition since the upper Eocene. A submergence of at least 560 ft occurred in the Pliocene(?), and coral reefs were built during the high stands of the sea during the interglacial epochs of the Pleistocene. No coral reefs predate the Pliocene, indicating that coral reefs are of fairly recent origin in this part of the Pacific.

Type specimens and identity of the described species of Conus III. The species described by Gmelin and Blumenbach in 1791

SUMMARY Of the 36 new species described by J. F. Gmelin in the 13th edition of the Systema Naturae, 15 are concluded to be valid, 15 are synonyms of previously described species, 5 are rejected as nomina dubia, and 1 is no longer placed in Conus. Gmelin described 8 new infraspecific taxa, of which 1 is considered valid and of species rank, 1 is a synonym of a previously described species, 4 are rejected as nomina dubia, and 2 are relegated to infrasubspecific status, as they are based not on allopatric populations but on morphologic variations without regard to geographic origin. The one new species described by J. F. Blumenbach in the 4th edition of his Handbuch der Naturegeschichte is concluded to be valid. As Gmelin probably possessed no specimens, but based his species on earlier published descriptions and figures, no original specimens exist. One neotype, 2 lectotypes, 8 representatives of holotypes and 21 representatives of lectotypes are selected and illustrated photographically. A representative of lectotype is selected for Blumenbach's species. By 1791, 97 species of Conus had been described, of which 62 are now considered valid. Of these 59 are Recent and 3 are Eocene fossils.

Late Eocene Multituberculates and Other Mammals from Wyoming

Isolated teeth of multituberculates have been found in association with late Eocene fossil mammals. Previous studies reported that multituberculates were not found in deposits younger than early Eocene age (Graybull provincial substage or equivalents). This newly found occurrence indicates that these animals are more likely to be late Eocene in age than reworked early Eocene materials.

On the geology of central Badakhshan (north-east Afghanistan)

Territory explored by the Italian geological expedition to Badakhshan during the summer of 1961 is described. The metamorphic rocks have been divided as follows: Faydzabad Gneiss, Qara Mughul Gneiss and Rabat Gneiss (pre-Devonian); Halqa Jar Amphibolite (from Devonian to Jurassic); black slates (undivided and probably of different ages). Besides these complexes there are several lithostratigraphic units, with semi-metamorphic facies. The igneous rocks are granite, granodiorite, quartz-diorite, and tonalite of three ages: Upper Permian-Lower Triassic, Upper Jurassic-Lower Cretaceous, and Tertiary. The sedimentary rocks, Cretaceous, Eocene, and Neogene, have been subdivided as follows: Shingan Formation, Qara Bulaq Formation, Mashad Limestone, Mohammad Aba Sandstone, Gazestan Formation, Baba Darwes Formation (marls and limestones with Cretaceous fossils), Kharakan Formation (with Eocene fossils), Kokcha Formation (Neogene), and Taluqan Gravel (Quaternary). Fluvio-glacial deposits, loess, alluvial and lacustrine deposits, landslides, and talus slopes, all Quaternary, are also present. Several formations border an old anticlinal core formed by the Faydzabad Gneiss. The anticline trends north-south. Groups of formations separated by unconformities are deformed to varying degrees of intensity.

Trees of the Past

A SHORT interpretation of the fossil herbaria of the rocks by the late Sir Albert Seward (J. Roy. Hort. Soc., 66, Pt. 6, June, 1941) provides a useful epitome of palæobotanical knowledge. The paper deals particularly with trees, and the story commences with Cercidiphyllum japonicum, an Eocene fossil species which is still indigenous in China and Japan. Cretaceous strata brought the first geological appearance of the genus Magnolia. Tulip–tree, plane, hazel and oak are present–day trees with stratigraphical antiquity. The maidenhair tree, Ginkgo biloba, is one of a group of plants which flourished in the Jurassic and Triassic periods. It is curious that many trees which now only appear in China and Japan were inhabitants of Europe and North America in earlier geological time; west and east seem to have changed places. The Norfolk Island pine, Araucaria excelsa, also had a divergent distribution in the past, for fossil leaves, cone scales and seeds were discovered in 1931 from Tertiary sediments in the Kerguelen Archipelago, where now is found only a scanty flora of flowering plants, ferns, mosses and lichens, but no trees.

Fauna of the Poul and Yakataga Formations (Upper Oligocene) of Southern Alaska

Introduction Very little is known about the marine Tertiary of Alaska. A number of marine fossils have been described from various localities, but the collections that have been made previous to 1920 are from scattered localities, and usually the material is not very well preserved. Grewingk2 described a few Tertiary species as early as 1850. In 1904 D all3 listed and described some marine Eocene fossils from the Alaska Peninsula. He also described a number of species from Miocene beds of the Shumagin Islands; the latter collections came from two localities, Unga Island and Popoff Island. Tertiary marine fossils have been reported from several localities along the coast of Alaska, and lists of species are given in various papers published by the United States Geological Survey. The determinations of the species in most of these lists, a large proportion of which are given as tentative, were made by Dall. In . . .

Rudbeckia and Aquilegia

WHEN recently (July) collecting Eocene fossils in the vicinity of Roan creek, Colorado, I saw for the first time the singular composite Rudbeckia montana Gray in life. It abounds in the valleys and gulches, occupying similar positions to those in which one finds R. laciniata on the eastern side of the range. The latter, so far as I could ascertain, is absent from the region of R. montana, though it occurs in the south-western part of Colorado. The striking feature of R. montana is the total absence of rays. The large conical or cylindrical discs appear very black, slightly yellow from pollen when in flower. The involucral bracts are coarse and pointed, surrounding the base of the disc and diverging at various angles. The whole effect is most peculiar and unusual. Rayless Compositae are known in various genera, and occasionally occur as mutations in normally rayed genera. The ancestor of R. montana was presumably rayed, but losing its rays through a germinal modification, how did it manage to survive and flourish to the exclusion of the rayed form?

Eocene fossils from Green River, Wyoming

Eocene fossils from Green River, Wyoming

Some new Eocene fossils from Alabama

Some new Eocene fossils from Alabama

Two new species of Eocene Fossils from the Lignitic of Alabama

Two new species of Eocene Fossils from the Lignitic of Alabama

Eocene Fossils at Murren

I HAVE read with surprise the extracts from the letter which you have received from Dr. Fellenberg on this subject. Of course it has long been known that there are Eocene strata at Murren. But below them lie calcareous rocks coloured on the Swiss map as Malm, These are so described on p. 211 of the “Livret Guide,” published by the International Geological Congress which met this autumn at Zürich. During the subsequent excursion, under the able guidance of Prof. Renevier, Prof. Golliez, and M. Lugeon, we were taken to Murren and shown these rocks, and Prof. Golliez gave us the reasons which had led some geologists to regard them as Trias rather than Malm. It was in these calcareous beds that the layer containing nummulites was met with. The train was just starting, and we had to leave, but the find excited so much interest that M. Lugeon returned to Murren the next day, with some of the party, and verified the exact locality.

Scientific Serials

American journal of Science, December.—An apparent time-break between the eocene and Chattahoochee miocene in southwestern Georgia, by Raphael Pumpelly. The Red Clay Hill region, a plateau extending through the south-western part of Georgia and adjacent northern Florida, has a maximum altitude of 300 feet, is sharply limited on the north by a declivity facing the eocene flat-land country, and consists of miocence deposits resting on eocene, both of which dip about 13 feet per mile to the south. The base of the plateau is formed by the white calcareous beds of the Chattahoochee group. A time-break between the latter and the eocene is evidenced by the almost general presence of a limestone conglomerate at the base of the Chattahoochee, immediately overlying eocene fossils, and the irregularity of the surface of demarcation. It seems possible that during miocene time the present plateau of southern Georgia was outlined by submerged islands of the eocene limestone. The Gulf Stream, after the creation of the central American barrier, found its way back to the Atlantic sweeping over southern Georgia and northern Florida, and supplying the food needed to build up the great organic beds of the Chattahoochee and Chipola. The lower flat-land country of central Georgia may represent the contemporaneous course of the cold current carrying less pure water and less nutriment.—The rise of the mammalia in North America, by H. F. Osborn. This second part deals with ancient and modern placental differentiation, the succession of the perissodactyls and the artiodactyls, a discussion of the factors of evolution, and a diagram illustrating the supposed descent of the mammalia from their Jurassic prototypes.—On the thoracic legs of Triarthrus, by C. E. Beecher. Some very perfect specimens of Triarthrus Becki, Green, in which nearly the entire calcareous and chitinous portions are represented by a thin film of iron pyrites, show, besides the antennæ already noticed, a complete series of thoracic legs becoming shorter towards the pygridium, but without any essential differences amongst each other. Each limb consists of two nearly equal members, one of which was evidently used for crawling, and the other for swimming. These two members and their joints may be correlated with certain typical forms of Crustacean legs among the Schizopoda, Cumacea, and Decapoda, and may be described in the same terms.—On the diamond in the Canon Diablo meteoric iron and on the hardness of carborundum, by George F. Kunz and Oliver W. Huntingdon. The carborundum made by Mr. Acheson, of Pittsburg, is capable of scratching most varieties of corundum, but not the diamond.

Das australische Florenelement in Europa

THIS is a defence of the identification of fossil plants from the Tertiary beds of Europe, chiefly from Austria and Hungary, with existing Australian genera. Baron Ettingshausen himself is largely responsible for these identifications, which have been questioned “by certain critics insufficiently acquainted with the subject.” He claims that he was supported in his views by such eminent palæontologists as Franz Unger and Oswald Heer. It is now some years since Unger published his sensational “Neuholland in Europa.” In this little work almost every one of a set of Eocene fossil plants is identified with some essentially Australian genus, and often, we should add, on the very slenderest of material. The late Mr. G. Bentham, who, as is well known, handled and described every Australian plant of which specimens had been collected up to his time, disputed the correctness of the identifications, and endeavoured to prove that the remains might well be those of genera still found in the northern hemisphere; yet Baron Ettingshausen gives us to understand that Mr. Bentharn confirmed his determination of a European fossil leaf as belonging to the genus Dryandra. Das australische Florenelement in Europa. Von Dr. Constantin Freiherr Ettingshausen. (Pp. 10. Tab. I. (Graz: Leuschner and Lubensky, 1890.)

Societies and Academies

LONDON Geological Society, June 6.—Mr. J. W. Hulke, F.R.S., president, in the chair.—George Paul was elected a Fellow of the Society. —The following communications were read: —The estuaries of the Severn and its tributaries, an inquiry into the nature and origin of their tidal sediment and alluvial flats, by Prof. W. J. Sollas, M.A., F.R.S.E., F.G.S. —Notes on a col lection of fossils and rock-specimens from West Australia, north of the Gascoyne River, by W. H. Hudleston, M.A., F.G.S. —Notes on the geology of the Troad, by J. S. Diller. Com municated by W. Topley, F.G.S. This paper gave a brief account of the results obtained by the author whilst attached to the United States Assos Expedition. Together with a geo logical map (scale 1: 100,000) this was sent to Mr. Topley for the service of the new geological map of Europe (and its bor ders), which is now being prepared by a Committee of the International Geological Congress. The country described is that lying south and west of the River Mendere (Scamander). The sedimentary rocks may be divided into three great groups: — I. An old, possibly Archaean, highly crystalline series, forming the mountainous lands of the Ida range (5750 feet), but also appearing in smaller detached areas to the west and north-west. Probably these have existed as islands from early times, and around these the later rocks have accumulated. Mount Ida itself is almost a dome, the lowestrocks (talcschists) occupyingthe summit. On the northern slopes there is true gneiss. No igneous rocks enter into the structure of this mountain. At different horizons there are bands of coarsely crystalline limestone, and as far as can be seen this series is conformable throughout. 2. Resting on these old rocks and in part made up of their remains is a series of partially crystalline rocks, chiefly limestone. It is probable that this series is in large part of Cretaceous age; but it contains rocks which are older, possibly Palaeozoic. Eocene fossils have lately been discovered by Mr. Frank Calvert, which also may have come from this series. The rocks in the south of the Troad, hitherto supposed to be Lower Tertiary, are now known to be of later date. Sharply marked off from these older rocks are the Upper Tertiaries; these are of two ages, occurring in two distinct areas. 3. The Upper Miocene, which fringes the western shores of the Troad, and forms a broader, band at the north-west corner in the lower course of the Mendere. Hissarlik is built on this. These beds are marine, and belong to the Sarmatmn Stage. The Troad is the most south-westerly point at which the Mactra-kalk is yet known. 4. Freshwater beds, which occur in force in the interior of the country, between the Menderé and the south coast, and in patches near the coast. These are Upper Miocene or Lowest Pliocene. Later than these are the Pliocene beds of the great plain of Edsemet The igneous rocks are of various ages, but most are of Tertiary date. The oldest is a granite which intrudes through and alters the oldest (? Archaean) crystalline rocks. This is invaded by dykes of Quartz-porphyry. Quartz-diorite invades and alters the group of partially crystalline rocks. The oldest rocks in the newer series are the Andesites and Liparites. These, in part, are older than the Sarmatian stage, as the conglomerate at its base con tains fragments of these rocks. But they are also in part of later date. Where they can be studied together the Liparite is the later of the two, as it flows through and carries up fragments of the Andesite. The Andesite (unlike the Liparite) seems to have reached the surface, in some cases, through volcanic vents. Basalts and Nepheline-basalts are of late Tertiary date; possibly they are the latest volcanic rocks of the district, but their relation to the other eruptive rocks of the Troad cannot be definitely determined. The volcanicjrocks in the isolated area between Alimadja and Lyalar are interesting because their relative ages are here well seen. The earliest was melaphyre; this was followed by mica-andesite, horneblende-andesite, augite-andesite, basalt, and late (if not last) by liparite. Mr. Topley, who in the absence of the author read the paper, explained the objects of the Assos Expedition and the geological results obtained by Mr. Diller. He gave a short account of previous literature, and mentioned some of the main points in which our knowledge of the Troad is now advanced. Mr. Topley briefly described the physical geography and general structure of the country, illustrating this by means of a section which he had prepared from Mr. Diller's map and paper.

Description of the Skull of a Dentigerous Bird ( Odontopteryx toliapicus , Ow.) from the London Clay of Sheppey

Amongst the additions to appear in the second edition of my ‘British Fossil Mammals and Birds’ I have anticipated the descriptions of certain species, as in the case of the gigantic Eocene bird, equalling in size the larger New-Zealand Moas. The still more remarkable Ornitholite, also from Sheppey, which I am now about to describe, has stronger claims to be made known, without delay, on account of the transitional character which it manifests to the Pterosaurian order. The fossil consists of a large portion of the skull, which, when the specimen was received in the British Museum, was more or less imbedded in the London Clay; the clearing out of the matrix by the careful and skilful hands of Mr. Davies, Senior Attendant in the “Geological Department,” brought to light the tooth-like processes of the alveolar borders of both upper and lower jaws, to which the uniqueness of this Eocene fossil is due; but the distinctive cranial characters of the warm-blooded feathered vertebrate are unmistakable. The well-developed brain, expanding transversely in its posteriorly placed box (P1. XVI. figs. 1-4, 3,7,11), making the base of a long cranial cone gradually tapering forward, the capacious lateral orbits ( ib. figs. 1, 2, 4, 0, 0), and the single hemispheroid condyle ( ib. fig. 3, 1) are avian: the large and long, freely articulated, dependent tympanic bone ( ib. figs. 1, 2, 3, 28), the slender, straight and styliform zygomatic bar ( ib. figs. 1 & 2, 26) received behind into the articular cup of the tympanic

On Upper Eocene Fossils from the Isle of Wight

As you wish me to give you my opinion respecting these Tertiary beds of the Isle of Wight, I will do it as fully as I can at present. I consider the upper formations of Hempstead to be the exact equivalent of those at Weinheim, Jeurres, and Bergh ( Rupélien inférieur , Dumont). I had already arrived at this opinion, on receiving from Saemann, in Paris, Voluta Forbesi , Edw., which Mr. Edwards himself considers as identical with V. Rathieri , together with some other fossils which have hitherto only been found in this horizon. The collection now sent adds Cerithium plicatum , with varieties, which Mr. Edwards calls C. subcostellatum , Forb., and C. inornatum , Morr.; also C. elegans , Desh. ( C. variabile , in the collection, and C. Austenii belong to the same species), C. Lamarckii , Brongn. (= C. Sedgwickii , Morr.), also Ostrea adlata , S. Wood (= O. cyathula , Lam., juv. ), Lucina Thierensi , Héb., Corbula subpisum , D'Orb., Panopæa minor , Forb. (= P. Heberti , Bosq., juv. ), Ostrea callifera , Lam., O. longirostris , Lam., Tellina Nystii , Desh. ( Tellina , sp. indeterm. in the collection), Lithodomus delicatulus , Desh. ( Modiola , sp. indeterm. in the collection), hitherto only known from Merigny, Waldböckelheim, and Alzey,—so that I now can no longer doubt that the upper beds of Hempstead accurately correspond with our “Marine Sand.” Much more difficult is it to make out the lower beds; I can at present only point out one horizon which corresponds with anything in Alsace or Germany—the freshwater limestone of Bembridge and Sconce═beds at Buxweiler (Alsace) and Abstadt (Baden).