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Grazing Periods And Forage Production On The National Forests, Arthur W. Sampson, Harry E. Malmsten Sep 1926

Grazing Periods And Forage Production On The National Forests, Arthur W. Sampson, Harry E. Malmsten

Aspen Bibliography

Stockmen in the West have always had confidence in the adequacy of the native forage crop to provide pasturage for their livestock. Indeed, under normal climatic conditions this enormous natural resource has not failed the grazier, except where it has been called upon to meet unreasonable demands. The productivity of the range has declined sharply, however, wherever the requirements of plant growth have been disregarded for many years in succession. Where there has been too early or too frequent and to heavy grazing, undue trampling, or some other unsatisfactory feature of range use, the results have been uniformly bad. Many …


The Natural Vegetation Of Ohio. Iii. Plant Succession, Paul B. Sears Jul 1926

The Natural Vegetation Of Ohio. Iii. Plant Succession, Paul B. Sears

Papers in Ecology

In the preceding papers of this series (1) it has been shown that within the glaciated area the physiographic results of glaciation offer the best general key to the pattern of natural vegetation. The results of glaciation, in turn, have been largely influenced by preglacial conditions.

In analyzing the composition of the natural vegetation of Ohio certain groups of associations were distinguished, to wit, Prairie, Ash, Oak, and Beech. Each group includes several related classical associations as described by Cowles (2) and others.


The Natural Vegetation Of Ohio Ii. The Prairies, Paul B. Sears May 1926

The Natural Vegetation Of Ohio Ii. The Prairies, Paul B. Sears

Papers in Ecology

It is well known that many treeless areas existed in Ohio before white settlement. These areas, of various ecological character and usually restricted in size, were in a few cases fairly extensive—embracing from fifty to one hundred square miles. The term "prairie" was rather generally applied to them, although more exact terms were not wanting. Like the various forest associations, these treeless areas have played an important role in influencing industrial and cultural phases of human life in Ohio (1). The present paper is an attempt to reconstruct such areas, now destroyed or obscured by secondary successions induced by white …


Directory Of Certain Alumni The Department Of Geology And Geography The University Of Nebraska, E. F. Schramm Jan 1926

Directory Of Certain Alumni The Department Of Geology And Geography The University Of Nebraska, E. F. Schramm

Bulletin of the University of Nebraska State Museum (1924–2023)

In the Department of Geology and Geography, The University of Nebraska, there have been over 10,000 registrants between the years 1891 and 1926. So many inquiries have been received concerning alumni and their addresses that it seems advisable to publish this directory. The list is necessarily incomplete since many of the alumni have not informed the Department respecting their addresses and change of positions. Out of the total number of those who have pursued professional vocations the following have kept in close touch with the Department.


Archidiskodon Maibeni, Erwin H. Barbour Jan 1926

Archidiskodon Maibeni, Erwin H. Barbour

Bulletin of the University of Nebraska State Museum (1924–2023)

Archidiskodon maibeni was first described in Bulletin 10 of the Nebraska State Museum under the title" Skeletal Parts of the Columbian Mammoth, Elephas Maibeni." * Dr. Henry Fairfield Osborn finds it expedient to found a new genus, Archidiskodon, to include the earlier and more primitive mammoths. Hence the change in the generic name. t'Mammoths and modern elephants have long been grouped together under 'the genus Elephas. Subdividing the genus does not necessarily do away with this convenient and rather familiar old arrangement.


An Ecological Study Of Timpanogos Creek From Aspen Grove To Wildwood, Marion L. Harris Jan 1926

An Ecological Study Of Timpanogos Creek From Aspen Grove To Wildwood, Marion L. Harris

Theses and Dissertations

Ecology may be oonsidered as one of the vital parts of botany, since there are two ultimate facts in this science; namely, the plant and its habitat . The habitat is made up of the physical factors that control function. At Timpanogos there are so many different habitats, that the chief problem is not that of finding a problem to study, but rather that of selecting one from the many. The purpose of this paper is to point out some of the interesting features that are found in a study of Timpanogos Creek from Aspen Grove to Wildwood.


The Natural Vegetation Of Ohio, Paul B. Sears May 1925

The Natural Vegetation Of Ohio, Paul B. Sears

Papers in Ecology

This map has been prepared by transcribing the species of bearing trees recorded by the original surveyors who traversed the Territory and State of Ohio before the destruction of the virgin forest by the hands of white men.

Surveying of Ohio was begun in July, 1786, (1) under The Geographer of the United States, Thomas Hutchins, employing for the first time his device of sections one mile square. This empirical device was hailed as a great American invention, although the State of Ohio has since been found to possess a curved surface in common with the rest of the earth. …


An American Fossil Giraffe, W. D. Matthew, E. H. Barbour Apr 1925

An American Fossil Giraffe, W. D. Matthew, E. H. Barbour

Bulletin of the University of Nebraska State Museum (1924–2023)

A fragment of the lower jaw of a large fossil mammal with two well-worn teeth was dug up in June 1918, at a depth of 20 feet, while digging a cess pool at Bradshaw, York County, Nebraska. This unique specimen, accessioned 7-7-18, was brought to the Nebraska State Museum by A. Archie Dorsey, and was donated by C. B. Palmet, both of Bradshaw. It undoubtedly occurred in loess, which is thickly as well. as extensively developed in this region. It is a ruminant jaw, the teeth preserved being P4 and m1. The characteristic pattern of the premolar excludes reference to …


Prosthennops Xiphodonticus, Sp. Nov.: A New Fossil Peccary From Nebraska, Erwin H. Barbour Apr 1925

Prosthennops Xiphodonticus, Sp. Nov.: A New Fossil Peccary From Nebraska, Erwin H. Barbour

Bulletin of the University of Nebraska State Museum (1924–2023)

During the field season of 1915, while collecting, a mile or two west of Valentine, Cherry County, Nebraska, Messrs. A. C. Whitford and J. B. Burnett secured for the Morrill-Maiben Palaeontological Collections, The Nebraska State Museum, The University of Nebraska, a finely preserved jaw of a small fossil hog, or peccary, belonging to the genus Frosthennops, accessioned No. 85-11-8-15B. & W.

The mandible under consideration was preserved in fine sand and is without blemish save that the condyle and coronoid are wanting. The dentition is perfect. In allusion to the sword-like tusks, which are unduly large, the species name xiphodonticus …


Sand Fulgurites From Nebraska Their Structure And Formative Factors, Abram E. Anderson Jan 1925

Sand Fulgurites From Nebraska Their Structure And Formative Factors, Abram E. Anderson

Bulletin of the University of Nebraska State Museum (1924–2023)

So much has been written during the past century on the origin, structure and occurrence of fulgurites, or lightning tubes, found in many parts of the world that it would seem as though little remains to be added to the literature on the subject; but the discovery of a considerable number of unusually large and complete specimens in Holt and Stanton Counties, Nebraska, which exhibit remarkable definition of the particular features that have occasioned so much controversy regarding their formative processes, has added an important type to the representatives of this phenomenon and afforded clearer interpretation of the origin of …


Skeletal Parts Of The Columbian Mammoth Elephas Maibeni, Sp. Nov., Erwin Hinckley Barbour Jan 1925

Skeletal Parts Of The Columbian Mammoth Elephas Maibeni, Sp. Nov., Erwin Hinckley Barbour

Bulletin of the University of Nebraska State Museum (1924–2023)

The skeletal parts of Elephas columbi are said to be unknown, although teeth, jaws, and skulls are common enough. Columbi is a mammoth of southern adaptation, hence its parts are found from Nebraska southward. Elephas columbi occurs abundantly throughout the State and many examples are preserved in the Nebraska State Museum, as will be seen in an accompanying list.


Tetrabelodon Abell, Sp. Nov., Erwin Hinckley Barbour Jan 1925

Tetrabelodon Abell, Sp. Nov., Erwin Hinckley Barbour

Bulletin of the University of Nebraska State Museum (1924–2023)

Brown County, Nebraska, which has been so prolific of long-jawed mastodons, has yielded another form which seems to be new and which may throw light on certain small tusks that occur where Tetrabelodon bones abound. Heretofore, we have considered these to be embryonic, but they show apparent wear, and in other respects they are enigmatic, and at best, atypical. Tetrabelodon tusks proper, however young, are typical, and are obviously tusks in miniature. The tusks in doubt are of varying lengths and about the diameter of one's thumb, but taper backwards, are worn to a bluntly oblique point, and are slightly …


Hackberry Conglomerate A New Nebraska Rock, Erwin Hinckey Barbour Jan 1925

Hackberry Conglomerate A New Nebraska Rock, Erwin Hinckey Barbour

Bulletin of the University of Nebraska State Museum (1924–2023)

In the cabinets of the Nebraska State Museum are several excellent rock specimens, which at first sight pass for pisolite, which they simulate. Scrutiny shows that they are hackberry seeds in sand, cemented by lime and clay into a firm, compact rock. The term hackberry conglomerate seems apropos.


Notes On Nebraska Fulgurites, Erwin Hinckley Barbour Jan 1925

Notes On Nebraska Fulgurites, Erwin Hinckley Barbour

Bulletin of the University of Nebraska State Museum (1924–2023)

Some six or eight years ago the writer contemplated a study of Nebraska fulgurites, both in the field and in the laboratory. In the meantime however, it proves to be superfluous for, after supplying Mr. A. E. Anderson, of the American Museum of Natural History, with certain material and data he proceeded in a masterful way on a technical inquiry, and it is with pleasure that, although delayed in publication, his findings follow in Bulletin 7 of the Nebraska State Museum. The present paper will deal as briefly as possible with the mode of occurrence and gross structure.


Sand Fulgurites From Nebraska Their Structure And Formative Factors, Abram E. Anderson Jan 1925

Sand Fulgurites From Nebraska Their Structure And Formative Factors, Abram E. Anderson

Bulletin of the University of Nebraska State Museum (1924–2023)

So much has been written during the past century on the origin, structure and occurrence of fulgurites, or lightning tubes, found in many parts of the world that it would seem as though little remains to be added to the literature on the subject; but the discovery of a considerable number of unusually large and complete specimens in Holt and Stanton Counties, Nebraska, which exhibit remarkable definition of the particular features that have occasioned so much controversy regarding their formative processes, has added an important type to the representatives of this phenomenon and afforded clearer interpretation of the origin of …


Manganese Fulgurites, Harold J. Cook Jan 1925

Manganese Fulgurites, Harold J. Cook

Bulletin of the University of Nebraska State Museum (1924–2023)

During August, 1924, while doing reconnaisance work near the head of Chugwater Creek, Wyoming, on the ranch of Mr. J. L. Jordon, the writer's attention was called to some unusual and interesting specimens found in a limited area, perhaps an acre or so, on the slope of the small butte flanking the Chugwater Valley. The hills of the region are of Tertiary age, the particular spot under consideration being Oligocene, the Brule stage, or Oreodon beds.


An American Fossil Giraffe Giraffa Nebrascensis, Sp. Nov., W. D. Matthew, E. H. Barbour Jan 1925

An American Fossil Giraffe Giraffa Nebrascensis, Sp. Nov., W. D. Matthew, E. H. Barbour

Bulletin of the University of Nebraska State Museum (1924–2023)

A fragment of the lower jaw of a large fossil mammal with two well-worn teeth was dug up in June 1918, at a depth of 20 feet, while digging a cess pool at Bradshaw, York County, Nebraska.


Elephas Scotti A New Primitive Mammoth From Nebraska, Erwin Hinckley Barbour Jan 1925

Elephas Scotti A New Primitive Mammoth From Nebraska, Erwin Hinckley Barbour

Bulletin of the University of Nebraska State Museum (1924–2023)

On February 18,1922, the mandible of an unusually primitive mammoth was secured for the palaeontological collections of Mr. Hector Maiben by Mr. E. T. Engle. The specimen was found in Aftonian gravel on the farm of Mr. E. J. Hartman, five miles south of Staplehurst, Seward County, Nebraska. It is numbered 18-2-22 in the accession book of the Nebraska State' Museum.


Elephas Scotti A New Primitive Mammoth From Nebraska, Erwin Hinckley Barbour Jan 1925

Elephas Scotti A New Primitive Mammoth From Nebraska, Erwin Hinckley Barbour

Bulletin of the University of Nebraska State Museum (1924–2023)

On February 18,1922, the mandible of an unusually primitive mammoth was secured for the palaeontological collections of Mr. Hector Maiben by Mr. E. T. Engle. The specimen was found in Aftonian gravel on the farm of Mr. E. J. Hartman, five miles south of Staplehurst, Seward County, Nebraska. It is numbered 18-2-22 in the accession book of the Nebraska State' Museum.


How To Study The Western Birds, Grace Mccormac French Jun 1924

How To Study The Western Birds, Grace Mccormac French

Jane Claire Dirks-Edmunds Documents

Originally a radio broadcast, this document explores the fraternal nature of bird watching. It was included in the papers of Dr. James A. Macnab, Dr. Jane Claire Dirks-Edmunds's mentor at Linfield College. The article mentions various books by bird-watching authorities and naturalists from around the Pacific Northwest.

Dirks-Edmunds, a 1937 graduate of Linfield, graduated from the University of Illinois in 1941; she returned to teach in the Biology department at Linfield from 1941-1974.


The Theory Of Spontaneous Generation, Arthur Thomas Kuesel Jun 1924

The Theory Of Spontaneous Generation, Arthur Thomas Kuesel

Bachelors’ Theses

The theories concerning the origin of life on this planet have been many and varied all down the ages. In the prescientific ages, if we may be allowed to designate those years as such, before science was as exacting and searching sit is now, practically all the theories advanced by the philosophers at the time have since been proven to be fallacies and all of them save one, the Theory of Spontaneous Generation have been discarded into the limbo of mistaken notions.


Extreme Evolution Is Absurd And Moderate Evolution Is Not Yet Established, Marie Georgiana Blommer Apr 1924

Extreme Evolution Is Absurd And Moderate Evolution Is Not Yet Established, Marie Georgiana Blommer

Bachelors’ Theses

In the world of literature and science many records containing startling theories are to be found. Among these is the doctrine of Evolution. Many assure us that Science compels us to believe in Evolution. An explanation of the terms must be clearly understood to avoid a fallacious use of terms. Professor Huxley, who follows Hume, declares that Science is "nothing but trained and organized commonsense." The term is applied to physical science or "that whose province is the observation of phenomena and inferences directly deducible from them." The term "Evolution" is often differently understood. In its literal sense it is …


A Preliminary Report On The Nebraska State Museum, Erwin H. Barbour Jan 1924

A Preliminary Report On The Nebraska State Museum, Erwin H. Barbour

Bulletin of the University of Nebraska State Museum (1924–2023)

The Nebraska State Museum has been established a sufficient number of years to make it widely known throughout the state, both by reputation and by personal visits. Incident to a growing clientele and an expanding correspondence, it is expedient that a concise circular letter be issued in bulletin form. Such a pamphlet can be promptly forwarded to inquirers and will offer obvious advantages over individual replies.


Root Behavior And Crop Yield Under Irrigation, Frank C. Jean, John E. Weaver Jan 1924

Root Behavior And Crop Yield Under Irrigation, Frank C. Jean, John E. Weaver

Papers of John E. Weaver (1884–1956)

More than half of the surface of the earth receives insufficient precipitation
for the most favorable growth of crops. The, best method of making up this deficiency is through the application of water by irrigation. Hence the economical use of irrigation water is one of the chief problems of agriculture in arid regions. Since much more land is available than can be irrigated by the supply of water, even when methods of greatest economy are employed, the welfare of these regions demands that the irrigation water be used as efficiently as possible (cf. Harris, 1916). It has been estimated that …


Some Field Instruments And Their Applications, G. W. Goldsmith Jan 1923

Some Field Instruments And Their Applications, G. W. Goldsmith

University Studies (University of Nebraska) (1888–1984)

Physiology and ecology depend for their constructive development largely upon the applications of physico-chemical concepts to living organisms and their environment, to their life processes, reactions, and interrelations. A concept is valuable biologically in so far as it can be applied and used as a tool for better understanding of the phenomena related to life. Ecology, as the study of the relations between organisms and their environment and of the interrelations of organisms, depends primarily upon the findings of physiology (Clements, 1905). But to apply physicochemical concepts and hence make them of value to the physiologist or ecologist commonly requires …


Variations In Cytology And Gross Morphology Of Taraxacum Ii. Senescence, Rejuvenescence, And Leaf Variation In Taraxacum, Paul B. Sears Jun 1922

Variations In Cytology And Gross Morphology Of Taraxacum Ii. Senescence, Rejuvenescence, And Leaf Variation In Taraxacum, Paul B. Sears

Papers in Ecology

The variability of Taraxacum has frequently been recorded in botanical literature without receiving much elucidation. It is less often an object of investigation than of conjecture and discussion. A few botanists have studied the effect of environmental factors upon Taraxacum, but their results have not cleared away taxonomic difficulties. Systematic botanists have either looked upon the variations in this genus as fluctuations or slight mutations, and then proceeded to lump or split as judgment might dictate. That life history exerts a profound influence upon form seems generally to have escaped attention.


Anthocyan Pigments, Paul B. Sears Jun 1922

Anthocyan Pigments, Paul B. Sears

Papers in Ecology

Noack has found rhamnose-free flavonol diglucosides to be much more abundant in green leaves than has generally been supposed. In such leaves as he studied he was able to establish the existence of flavonol-anthocyan in couples of similar glucosidal nature, but secured no evidence of aromatic nucleus composition in such cases. He suggests that these couples function as a reduction mechanism during photosynthesis.


Variations In Cytolgoy And Gross Morphology Of Taraxacum, I. Cytology Of Taraxacum Laevigatum, Paul B. Sears Apr 1922

Variations In Cytolgoy And Gross Morphology Of Taraxacum, I. Cytology Of Taraxacum Laevigatum, Paul B. Sears

Papers in Ecology

These investigations are the outgrowth of a study, begun in 1914 at the instance of the late Professor C. E. Bessey, of parthenogenesis in Taraxacum vulgare (Lam.) Schrk. and T. laevigatum ( Willd.) DC. These two species are the common ones in central United States, being respectively designated as Leontodon taraxacum L. and L. erythrospermum (Andrz.) by Britton and Brown (3). In 1917 the existence of ameiotic parthenogenesis in both species was confirmed (23) and certain pollen abnormalities briefly described. These abnormalities have invited more critical analysis as a means of throwing light upon certain phases of variation …


Vegetation Mapping, Paul B. Sears Apr 1921

Vegetation Mapping, Paul B. Sears

Papers in Ecology

The value of accurate maps of native vegetation as a basis for very practical generalizations can not be questioned. It is obvious that an essential condition for getting accurate maps of large areas is the existence of precise maps of smaller component ones. At present very few precise local maps are available, but it is to be hoped that botanists throughout the country will begin to supplement the efforts of a few of their number who are doing map work of permanent and general' value.


Variation In Taraxacum, Paul B. Sears Feb 1921

Variation In Taraxacum, Paul B. Sears

Papers in Ecology

To the editor of Science: Since several species of Taraxacum are parthenogenetic and at the same time highly variable they have. looked like tempting material for the study of certain phases of genetics. Moreover their "polysnorphy," as well as that of other parthenogenetic plants, has served as a partial basis for well-known attempts to explain parthenogenesis as due to hybridization.