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Articles 14821 - 14850 of 14916

Full-Text Articles in Physical Sciences and Mathematics

The Geologic History Of The Bison In The Great Plains (A Preliminary Report), C. Bertrand Schultz, W. D. Frankforter Dec 1946

The Geologic History Of The Bison In The Great Plains (A Preliminary Report), C. Bertrand Schultz, W. D. Frankforter

Bulletin of the University of Nebraska State Museum

THE GEOLOGIC history of the bison in North America is a subject which has received little attention to date. Osteological rather than geological problems have been the main concern of most writers who have so far published. If the geologic history of the bison is to be learned, it will be necessary to devote more time and effort in the field in determining the age of the deposits in which various specimens have been discovered and in making more extensive collections from deposits of known age. Unfortunately the majority of the type specimens have been surface finds and little attempt …


Tertiary Coniferous Woods Of Western North America, George F. Beck Aug 1945

Tertiary Coniferous Woods Of Western North America, George F. Beck

All Faculty Scholarship for the College of the Sciences

Almost four decades have elapsed since Platen (1908), the German paleobotanist, published his report upon the fossil woods of the western United States. Since then no over-all treatment of these materials has been attempted. although Platen overlooked the Pacific Northwest with its abundance of Tertiary petrified woods. The purpose of this paper is to bring knowledge of the western coniferous woods of the Tertiary up to date. In this effort the writer recognizes that much of this information has been accumulated incidentally in the study of the Russell Petrified Forest series of central Washington, and that it is not as …


Range Land Of America And Some Research On Its Management, Laurence A. Stoddart Apr 1945

Range Land Of America And Some Research On Its Management, Laurence A. Stoddart

Faculty Honor Lectures

Although grazing of livestock has been a practice and a profession of man almost from his beginning only recently has range management reached anything approaching a pre~ cise science. Although ' trials and errors over the years brought to light much practical methodology for assuring high production from grazing land, still it remained for the plant physiologist and ecologist to find the whys and wherefores, and to advance new methods and new thoughts which promise to increase productivity still further and at the same time maintain the great range resource.

The peculiar land situation that marked America in her forma~ …


Progress Report On The Ground-Water Resources Of The Las Vegas Artesian Basin, Nevada, George B. Maxey, C. Harry Jameson Mar 1945

Progress Report On The Ground-Water Resources Of The Las Vegas Artesian Basin, Nevada, George B. Maxey, C. Harry Jameson

Publications (WR)

Whether the tremendously increased population acquired by Las Vegas in the years 1940 to 1942 will be retained cannot at present be foretold. However, the valley will undoubtedly be expected to support a considerably larger population than it did at any time prior to 1940, and continually increasing demands on the water supply for innumerable pcacetimc activities must be anticipated. Therefore, a sound evaluation of tho ground water resources of Las Vegas Valley is directly in line with the other wisely progressive planning programs which are now operating or are taking shape in the valley as well as in the …


Nyssa Woods Of The Pacific-Northwest Tertiary, George F. Beck Feb 1945

Nyssa Woods Of The Pacific-Northwest Tertiary, George F. Beck

All Faculty Scholarship for the College of the Sciences

The nyssa gums are one of the modern genera of trees most certainly present among the petrified woods and forests of the Pacific Northwest. Almost every collection from the mid-Tertiary of this region contains a few specimens of typical tupelo or sour gum. These are fine-grained woods which to the unaided eye may be mistaken for conifers.


The Yale Forest In Tolland And Windham Counties, Connecticut, Walter H. Meyer, Basil A. Plusnin Jan 1945

The Yale Forest In Tolland And Windham Counties, Connecticut, Walter H. Meyer, Basil A. Plusnin

Yale School of the Environment Bulletin Series

No abstract provided.


Ancient Maples Of The Central Washington Region, George F. Beck Nov 1944

Ancient Maples Of The Central Washington Region, George F. Beck

All Faculty Scholarship for the College of the Sciences

When I began work on the petrified logs of the general Vantage area some 13 years ago, it became apparent at once that maple-like woods are commonplace in the main (Vantage) raft forest and slightly less abundant in two rooted units of the Yakima Canyon. So widely do these woods range throughout the structural variations found in modern maples that little success has attended the efforts to assign them to nominal species. The extremes can readily be established but few hints exist as to the boundaries between them.


Two Newly Discovered Conifers, George F. Beck Apr 1944

Two Newly Discovered Conifers, George F. Beck

All Faculty Scholarship for the College of the Sciences

Two genera of coniferous wood, apparently not listed among the Tertiary woods of the western states, have been recognized in the Percy Train collections from Rainbow Ridge, northwestern Nevada. These two, Tsuga (hemlock) and Chamaecyparis (cedar) bring up to 14 the genera of coniferous wood more or less certainly identified from the period and area in question.


Status Of Tertiary Woods Of The Western States Representing The Juglandaceae, George F. Beck Apr 1944

Status Of Tertiary Woods Of The Western States Representing The Juglandaceae, George F. Beck

All Faculty Scholarship for the College of the Sciences

For many years there has been uncertainty concerning the generic status of some fossil leaves belonging without question to the walnut family as a whole. A review of the woods of Juglandaceae as they have appeared in Tertiary horizons of the western states has suggested which genera are present, and in what proportions their leaves (or other remains) might be expected to appear.


Volume Tables For Connecticut Hardwoods, Walter H. Meyer, Raymond Kienholz Jan 1944

Volume Tables For Connecticut Hardwoods, Walter H. Meyer, Raymond Kienholz

Yale School of the Environment Bulletin Series

No abstract provided.


Nitrate Production As Affected By Grain-Crop Residues On The Surface Of The Soil, T. M. Mccalla, J. C. Russel Aug 1943

Nitrate Production As Affected By Grain-Crop Residues On The Surface Of The Soil, T. M. Mccalla, J. C. Russel

Historical Research Bulletins of the Nebraska Agricultural Experiment Station

The purpose of this bulletin is to present the data on nitrate contents and nitrate production in tests where straw or stalk residues were left on the surface through subsurface tillage, as compared with check treatments where these residues were plowed under or were absent. Nine of these tests were at Lincoln, Nebraska, and one was at the Hastings, Nebraska, Hydrological Project. Two tests were conducted in 1939, four in 1941, and four in 1942.


White Pine Blister Rust In Western North America, J. L. Mielke Jan 1943

White Pine Blister Rust In Western North America, J. L. Mielke

Yale School of the Environment Bulletin Series

No abstract provided.


Establishment, Development, And Management Of Conifer Plantations In The Eli Whitney Forest, New Haven, Connecticut, Ralph C. Hawley, Harold J. Lutz Jan 1943

Establishment, Development, And Management Of Conifer Plantations In The Eli Whitney Forest, New Haven, Connecticut, Ralph C. Hawley, Harold J. Lutz

Yale School of the Environment Bulletin Series

No abstract provided.


Vegetation Of The Northern Part Of Cherry County, Nebraska, William L. Tolstead Jul 1942

Vegetation Of The Northern Part Of Cherry County, Nebraska, William L. Tolstead

Conservation and Survey Division

Agricultural practices in the Great Plains of North America are now in a period of adjustment from a traditional agriculture initiated by pioneer farmers to a grazing economy based upon potentialities of climate and soil. The attainment of a proper system of land use has been retarded in many localities by the lack of definite information concerning the vegetation and its indicator significance. In this study of the vegetation of Cherry County, Nebraska, the interrelations between the plants and their environments are discussed, the dominant species are described, and changes in grasslands caused by seasons, grazing, and climatic cycles are …


Range Sheep Industry In Kittitas County, Washington, Reginald M. Shaw Apr 1942

Range Sheep Industry In Kittitas County, Washington, Reginald M. Shaw

Geography Faculty Scholarship

This article summarizes the sheep industry in Kittitas County, Washington State as a microcosm of the entire Pacific Northwest sheep industry.


Decay Of Western Hemlock In Western Oregon And Washington, G. H. Englerth Jan 1942

Decay Of Western Hemlock In Western Oregon And Washington, G. H. Englerth

Yale School of the Environment Bulletin Series

No abstract provided.


Yield Of Even-Aged Stands Of Loblolly Pine In Northern Louisiana, Walter H. Meyer Jan 1942

Yield Of Even-Aged Stands Of Loblolly Pine In Northern Louisiana, Walter H. Meyer

Yale School of the Environment Bulletin Series

No abstract provided.


Growing Of White Pine On The Yale Forest Near Keene, New Hampshire, Ralph C. Hawley, Robert T. Clapp Jan 1942

Growing Of White Pine On The Yale Forest Near Keene, New Hampshire, Ralph C. Hawley, Robert T. Clapp

Yale School of the Environment Bulletin Series

No abstract provided.


Management Of Loblolly Pine In The Pine-Hardwood Region In Arkansas And In Louisiana West Of The Mississippi River, Herman H. Chapman Jan 1942

Management Of Loblolly Pine In The Pine-Hardwood Region In Arkansas And In Louisiana West Of The Mississippi River, Herman H. Chapman

Yale School of the Environment Bulletin Series

No abstract provided.


The Geographic Distribution Of Azotobacter And Rhizobium Meliloti In Nebraska Soils In Relation To Certain Environmental Factors, H. B. Peterson, T. H. Goodding Jun 1941

The Geographic Distribution Of Azotobacter And Rhizobium Meliloti In Nebraska Soils In Relation To Certain Environmental Factors, H. B. Peterson, T. H. Goodding

Historical Research Bulletins of the Nebraska Agricultural Experiment Station

In this investigation a survey of Nebraska soils has been made in order to determine the distribution of the aerobic nonsymbiotic and symbiotic nitrogen fixers of the genera Azotobacter and Rhizobium respectively. In connection with this survey, some of the characteristics of the soils which may bring about this distribution were studied. Up to this time practically no research has been reported on the microflora of the soils of Nebraska. Hence there is little basis for predicting the activity of these organisms under environmental conditions as they exist here. It is hoped that this work will not only supply some …


The Pipy Concretions Of The Arikaree, C. Bertrand Schultz Jan 1941

The Pipy Concretions Of The Arikaree, C. Bertrand Schultz

Bulletin of the University of Nebraska State Museum

The pipy concretions of the Arikaree (lower Miocene) of Nebraska and adjacent states were first described by Nelson Horatio Darton (1899, p. 743) as "characteristic layers of hard, fine-grained, dark-gray concretions, often consisting of aggregations of long, irregular, cylindrical masses" (see Figures 30, 32, 34, and 35). The individual pipes vary in diameter from a few inches to several feet, and in length from a few inches to a hundred yards or more. Tests demonstrate that pipy concretions are composed of sand cemented by calcium carbonate. When dipped in acid the cement is dissolved and the concretion is reduced to …


The Ancestral Ursid, Hemicyon, In Nebraska, Edwin H. Colbert Jan 1941

The Ancestral Ursid, Hemicyon, In Nebraska, Edwin H. Colbert

Bulletin of the University of Nebraska State Museum

During the summer of 1928, a University of Nebraska State Museum field party, composed of Dr. A. L. Lugn and the writer, made a collection of upper Miocene and lower Pliocene mammals in Brown and Cherry counties, Nebraska. This collection was sponsored and made possible by the generosity of the late Hon. Charles H. Morrill.


A New Fossil Bovid From Nebraska With Notice Of A New Bison Quarry In Texas, C. Bertrand Schultz Jan 1941

A New Fossil Bovid From Nebraska With Notice Of A New Bison Quarry In Texas, C. Bertrand Schultz

Bulletin of the University of Nebraska State Museum

An interesting and unique bovid skull was reported to the staff of the University of Nebraska State Museum in 1938 by Mr. Alvin McReynolds of Nehawka, Nebraska. The specimen was found in 1933 in a ravine north of Nehawka by Messrs. Merritt and Harold Dodson, brothers. Although the skull was not in place, it appears to have been washed out of a nearby Pleistocene clay deposit by floodwaters. The specimen is well preserved and is of a dark brown, almost black color. In 1938 it was loaned to the Museum for study and photographing but was not obtained as a …


Penetration Of The Walls Of Wood Cells By The Hyphae Of Wood-Destroying Fungi, Phimister Proctor Jr. Jan 1941

Penetration Of The Walls Of Wood Cells By The Hyphae Of Wood-Destroying Fungi, Phimister Proctor Jr.

Yale School of the Environment Bulletin Series

No abstract provided.


A Shovel-Tusked Mastodon, Arnebelodon Fricki, From Kansas, Erwin Hinckley Barbour, Claude W. Hibbard Jan 1941

A Shovel-Tusked Mastodon, Arnebelodon Fricki, From Kansas, Erwin Hinckley Barbour, Claude W. Hibbard

Bulletin of the University of Nebraska State Museum

Since the Amebelodontinae were first announced (Barbour 1927), a number of examples of the genus Amebelodon have presented themselves in various parts of Nebraska, Colorado, and in several places in Kansas. Thus its range has already been materially extended, many skeletal parts added, and the hope kindled that knowledge of this remarkable group of proboscideans is destined to be greatly enriched within the next few years. As may be seen in the accompanying lists of the known parts of Amebelodon preserved in various museums, there are already at hand the bones necessary for the assemblage of a nearly complete composite …


A New Species Of Sphenophalos From The Upper Ogallala Of Nebraska, Erwin Hinckley Barbour, C. Bertrand Schultz Jan 1941

A New Species Of Sphenophalos From The Upper Ogallala Of Nebraska, Erwin Hinckley Barbour, C. Bertrand Schultz

Bulletin of the University of Nebraska State Museum

The genus Sphenophalos was described by John C. Merriam (1909, p. 319-30), who based his description on a fragmentary horn-core (Uni. of Calif. No. 11887) from the late Tertiary deposits near Thousand Creek in northern Humbolt county, Nevada. Knowledge of Sphenophalos, however, is still confined to this single, fragmented type horn-core (Frick 1937, p. 472) and other fragmental specimens (Furlong 1932, p. 27-36).


Disturbance Of Forest Soil Resulting From The Uprooting Of Trees, Harold J. Lutz Jan 1940

Disturbance Of Forest Soil Resulting From The Uprooting Of Trees, Harold J. Lutz

Yale School of the Environment Bulletin Series

No abstract provided.


Asterolecanium Variolosum Ratzeburg, A Gall-Forming Coccid, And Its Effect Upon The Host Trees, Thaddeus Parr Jan 1940

Asterolecanium Variolosum Ratzeburg, A Gall-Forming Coccid, And Its Effect Upon The Host Trees, Thaddeus Parr

Yale School of the Environment Bulletin Series

No abstract provided.


A New Giant Camel Gigantocamelus Fricki, Gen. Et Sp. Nov., Erwin Hinckley Barbour, C. Bertrand Schultz Jan 1939

A New Giant Camel Gigantocamelus Fricki, Gen. Et Sp. Nov., Erwin Hinckley Barbour, C. Bertrand Schultz

Bulletin of the University of Nebraska State Museum

A lower Pleistocene deposit containing fossil vertebrates near Broadwater, Morrill county, Nebraska, has been reported upon by the writers, beginning three years ago. Five fossil quarries have been opened since the site was discovered in 1936.


The White River Oligocene Rodent Diplolophus, Erwin Hinckley Barbour, Thompson M. Stout Jan 1939

The White River Oligocene Rodent Diplolophus, Erwin Hinckley Barbour, Thompson M. Stout

Bulletin of the University of Nebraska State Museum

The rich and varied nature of the mammalian faunas of the White River Oligocene has been recognized for many years, but the exact geologic succession is only now becoming known. In these faunal assemblages the rodents and lagomorphs appear to have been important elements, perhaps numerically as abundant in the Oligocene as are these same groups at present.