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Showing posts with label Palaeontology. Show all posts
Showing posts with label Palaeontology. Show all posts

1940: Palaeontology, Vertebrate

Field Work.

This was a year of unusual field activity on the part of all of the large museums and many of the smaller institutions, some of which were conducting explorations for the first time.

On the Pacific Coast the University of California, at Berkeley, continued its researches into the Triassic of Arizona and the later Tertiaries of northern California. The California Institute of Technology at Pasadena made the surprising discovery of the skeleton of a trachodont dinosaur in the Cretaceous of the southern San Joaquin Valley. Aside from a single trachodont tooth from the same general locality this is the only evidence of dinosaurs from the Pacific Coast region.

The Field Museum of Chicago had a successful expedition into the later Tertiaries of the Rocky Mountain region and the State Museum of the University of Nebraska, at Lincoln, and conducted eight expeditions into the Pleistocene and Pliocene of Nebraska, New Mexico and Arkansas. The famous Conard Fissure, in Arkansas, explored many years ago by the American Museum, was reopened and a great quantity of Pleistocene fossils secured.

In South Dakota the State School of Mines, with the cooperation of the National Geographic Society, secured a great collection of Oligocene fossils from the Channel Sandstone of the Big Badlands. These great Badlands of the Black Hills region were visited, during the season, by eight or ten collecting parties from as many institutions.

A National Museum party revisited the classic Middle Eocene exposures of the Bridger Basin in southwest Wyoming and secured an important collection. Princeton University explored various parts of the Rocky Mountain region, obtaining an important Paleocene fauna from Montana and a unique specimen of a complete and perfectly preserved bat from the Eocene Green River shales of western Wyoming.

The American Museum of Natural History sent out two expeditions. One party explored the Big Badlands of South Dakota, for the fourth successive season, finding, among other things, a remarkable relict of an Eocene line of rodents of the Paramys group. This party also obtained from the latest Cretaceous deposits of southeastern Montana a unique dinosaur skull related to Troƶdon. In Texas the second party explored the Cretaceous of the Big Bend country and, from near Fort Worth, excavated a series of tracks of the great sauropod dinosaurs.

The University of Texas, with the aid of the WPA, carried out most extensive reconnaissance and collecting activities throughout the State.

Exhibitions.

Exhibitions in the various museums of the country during the year have hardly kept pace with the unusually intensive field work, but several noteworthy exhibits have been installed. At Harvard, in the Museum of Comparative Zoology, the exhibits have been enriched by the addition of primitive reptiles from the southwest and from Brazil. At the American Museum there have been added mounted skeletons of the reptilian Pareiasaurus from Russia and the mammalian Aardvark from the Island of Samos.

At the Field Museum, the Hall of Vertebrate Palaeontology has been improved by the addition of some new material and a rearrangement of the old. At Lincoln the already great collection of proboscideans has been enlarged by a skeleton of the Hairy Mammoth from Illinois. The National Museum shows, probably, the greatest change in its exhibition hall, largely through increased exhibition space.

Research and Publications.

D. H. Dunkle and P. Bungart published a paper describing some of the important Devonian arthrodires in the Cleveland Museum. The former of these two authors also described the cranial osteology of a Cretaceous fish from Brazil.

One of the most important contributions of the year was the definitive monograph of the Permian Pelycosauria, by A. S. Romer and L. I. Price, a work representing many years of intensive research upon this group of reptiles. T. E. White discussed the classification of the plesiosaurs, and in another paper described some new Miocene vertebrates from Florida. B. Brown and E. Schlaikjer published an important paper describing in detail the osteology of the primitive ceratopsian dinosaur, Protoceratops, and in two other papers these authors discussed certain problems of ceratopsian morphology. The ceratopsians were also considered by C. M. Sternberg, who described members of this group from Alberta. This same author in another paper discussed the classification of the hypsilophodont dinosaurs.

R. M. Sternberg described a toothless bird from the Cretaceous of Alberta, while A. Wetmore described birds from the Pleistocene of Java, associated with certain types of primitive men. H. Howard and A. H. Miller described birds associated with human remains at Ranch La Brea, California.

G. L. Jepsen published an important paper describing a Paleocene mammalian fauna from Wyoming. R. W. Wilson, in a series of papers, described various rodents from the Eocene and later Tertiary of California. W. B. Scott brought out his study of the Artiodactyla from the White River Oligocene beds of North America, another part of the large monographic revision of the White River fauna being done by and under the supervision of this authority. H. E. Koerner published the first of a series of papers describing the stratigraphy and faunas of Montam Miocene formations. C. B. Schultz and C. Falkerbach published a paper on the merycochoerine oreodonts. The osteology of a camel from the John Day beds was described by J. F. Dougherty. E. H. Colbent discussed certain Miocene deer from Mongolia, and in another contribution described a new Lower Pleistocene fauna from Yunnan, China. Important papers describing new Miocene mammalian faunas from California were published by P. C. Henshaw, J. F. Dougherty and R. H. Jahns. V. L. VanderHoof and J. T. Gregory published a review of the carnivore genus, Aelurodon, while R. A. Stirton described a supposed hyaenid from the Pliocene of Texas. This latter author also discussed, in another paper, the phylogeny of the North American Equidae. C. J. Hesse described a Pliocene fauna from Texas.

E. C. Olson described a Pleistocene fauna from Missouri, and in another paper discussed the cranial foramina in North American beavers, fossil and recent.

H. Seton described two new primates from the Eocene Wyoming. G. G. Simpson, in an important paper, discussed certain problems with regard to early Tertiary primates. This same author published a comprehensive review of the mammal-bearing Tertiary beds of South America, and in another paper considered the problem of past mammalian 'migrations' in the light of present-day evidence. E. H. Sellards published a complete and detailed index to all of the localities in North America where early man has been found associated with extinct mammals. This same author described a locality in Texas where artifacts were found associated with Pleistocene mammals, many of types now extinct. In addition this author described a new Pliocene mastodon from Texas.

A work that will prove very useful to Palacontologists in the future was the bibliography of literature on vertebrate palaeontology between the years 1928 and 1933, published by C. L. Camp and V. L. VanderlHoof. See also ANTHROPOLOGY.

1939: Palaeontology, Vertebrate

Field Work.

The California Institute of Technology continued its search of the Lower Oligocene Sespe beds of Southern California with gratifying results. At Berkeley the University of California group made their annual expedition to the Triassic of Arizona and New Mexico and continued their delving into the Pliocene faunas of Nevada and Northern California. Intensive work in the Late Tertiaries of the western part of the state was carried on by the museum staff of the University of Nebraska.

Field Museum of Chicago sent successful expeditions into the Pliocene of South Dakota and into the Palaeocene beds of Colorado and the Carnegie Museum of Pittsburgh continued the work it has been carrying on for years in the Upper Eocene of northeastern Utah. The National Museum continued its work in the Paleocene of Central Utah and Princeton University again explored the Lower Eocene of the Big Horn Basin, Wyoming.

Harvard University added materially to its collection by an expedition into the Permian of Texas, and the American Museum for the third consecutive season collected in the Oligocene deposits of western South Dakota and did reconnaissance work in the Cretaceous of Texas, Montana and Alberta.

The State of Texas, with WPA assistance, inaugurated a statewide reconnaissance program for the purpose of locating important fossil bearing formations and localities.

Exhibitions.

Of first importance was the opening at the American Museum in New York of the so-called Jurassic Hall, in which there is a new geological arrangement of amphibians and reptiles from the Carboniferous to the Basal Cretaceous.

In the old dinosaur hall there is a rearrangement of Upper Cretaceous dinosaurs and the installation of new exhibits of pterosaurs, turtles, crocodiles and birds. The corridor connecting these two halls now contains the marine reptiles and dinosaur tracks. A remarkable skeleton of the Early Pleistocene gaur, from China, has been placed in the Tertiary Hall.

At the Academy of Natural Sciences of Philadelphia a new hall devoted to the earth sciences, including vertebrate palaeontology, was opened. The Harvard Museum placed on exhibition a skull of the giant Australian plesiosaur Kronosarus and added to its exhibition of Brazilian Triassic reptiles; at Field Museum several skeletons of Tertiary mammals were installed and a complete rearrangement of their fossil vertebrate collection was begun.

The Colorado Museum of Natural History in Denver has completed a skeleton of the plated dinosaur Stegosaurus and the University Museum at Lincoln. Neb., has added to its already remarkable collection of Nebraska fossils a skeleton of the greatest of all camels Gigantocamelus.

Under this heading should be mentioned the progress toward completion of work on the Dinosaur National Monument of northeastern Utah where, eventually, there will be shown, under glass roofs, complete skeletons of the great Sauropod dinosaurs worked out in high relief against their rocky beds.

Research and Publications.

A publication of great interest to vertebrate palaeontologists was the autobiography of the dean of American Palaeontologists, Professor William B. Scott, A. S. Romer continued his studies on late Paleozoic branchiosaurs, and in addition, described the first-known cotylosaurian egg. One of the most important palaeontological papers of the year was the monographic study by T. E. White of the complete skeleton of Seymouria, an exceptionally important vertebrate from the evolutionary standpoint. R. L. Nace described the first Cretaceous ichthyosaur known in North America from adequate remains. C. W. Gilmore made an additional contribution to the study of the ceratopsian dinosaurs, while active research on this group was continued by B. Brown and E. M. Schlaikjer.

W. K. Gregory and M. Hellman contributed a valuable study upon the relationships and anatomy of the South African man-apes, discovered by R. Broom; G. G. Simpson with the collaboration of A. Roe, published 'Quantitative Zoology,' a definitive textbook applying for the first time the use of statistical methods to the study of fossil and recent animals; G. L. Gazin continued his work on the Dragon Paleocene formation of Utah, which has yielded a new and important fauna; B. Patterson continued his series of papers dealing with proto-ungulates; E. H. Colbert described Miocene horses and carnivores of Mongolia and in addition, with R. Chaffee, contributed a study on the evolution of antilocaprids. A. L. Lugn made a definitive study of the sequence of Tertiary mammal-bearing deposits in Nebraska; E. H. Barbour and C. B. Schultz described a new, gigantic camel, by far the largest camelid known, from the Pleistocene of that state; R. A. Stirton made a detailed study of all of the fossil mammals from the San Francisco Bay region, and in addition considered the problems of holarctic correlation as based upon mammals; a paper of general interest was Gaynor Evan's study of the evolution of the atlas-axis complex, from fish to mammal. See also GEOLOGY; SEISMOLOGY.