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Articles 32581 - 32610 of 32961

Full-Text Articles in Life Sciences

The Mandibular Tusks Of Amebelodon Fricki, Erwin H. Barbour Jan 1929

The Mandibular Tusks Of Amebelodon Fricki, Erwin H. Barbour

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

The ponderous mandible of the great shovel-tusked mastodon, Amebelodon fricki, was figured and described before it was practicable to remove the plaster cinches. In the meantime, this rare specimen has lain on its sand table awaiting the time when sections and casts could be made before mounting it permanently. A rare specimen, especially if heavy, unwieldy, and fragile, is rarely dismantled for study after it is mounted and installed in its case. A gelatine cast of the alveoli has been made, and through the assistance of Mr. Murray Jerome Roper, a cast of the left mandibular tusk has just been …


The Frequency Of Somatic Mutation In Variegated Pericarp Of Maize, R. A. Emerson Jan 1929

The Frequency Of Somatic Mutation In Variegated Pericarp Of Maize, R. A. Emerson

Department of Agronomy and Horticulture: Faculty Publications

Some years ago (Emerson 1922) the writer announced that in F2 of

certain crosses of variegated with colorless pericarp in maize the heterozygous

individuals changed to self color more frequently than did the homozygous

individuals of the same cultures. No “explanation” of this phenomenon

was then apparent, but later results, though still far from affording

an adequate solution of the problem, have furnished at least a working

hypothesis. The original unpublished paper, with minor modifications,

is given below, under the heading. “Somatic mutations in heterozygous

and in homozygous variegated pericarp.”


The Insects And Mites Injurious To Poultry In Nebraska And Their Control, M. H. Swenk, F. E. Mussehl Dec 1928

The Insects And Mites Injurious To Poultry In Nebraska And Their Control, M. H. Swenk, F. E. Mussehl

Nebraska Agricultural Experiment Station: Historical Circulars

There are a number of different kinds of insect and mites (arthropods) that are more or less injurious to poultry in Nebraska. This circular is designed to give practical information concerning these pests and their control.


Experimental Studies Of Cultivation Of Certain Vegetable Crops, J. E. Weaver Apr 1928

Experimental Studies Of Cultivation Of Certain Vegetable Crops, J. E. Weaver

Department of Agronomy and Horticulture: Faculty Publications

For those who have an interest in the ecology of cultivated plants, Thompson's experimental studies on vegetable crops has a wealth of information. This memoir deals not only with the effect of cultivation on yield, but analyzes the several factors of soil moisture, soil temperature, and the production of nitrates as affected by cultivation, and the effect of weeds on these factors. Finally the root habits are studied, and a correlation is made between the root system and the response of the plant to cultivation.


Spraying Tree Fruits, C. C. Wiggans, E. H. Hoppert Mar 1928

Spraying Tree Fruits, C. C. Wiggans, E. H. Hoppert

Nebraska Agricultural Experiment Station: Historical Circulars

The production of sound, clean fruit is unquestionably one of the major problems facing the modern fruit grower. Culture may be neglected and pruning delayed for a time but the omission of sprays for even a single season demonstrates their absolute necessity. This applies equally to the commercial grower and to the farmer or gardener who has only a few trees.


Ec28-234 Nebraska System For Tattooing Hogs For Identification After Slaughter, G.R. Boomer, O.O. Waggener Jan 1928

Ec28-234 Nebraska System For Tattooing Hogs For Identification After Slaughter, G.R. Boomer, O.O. Waggener

University of Nebraska-Lincoln Extension: Historical Materials

A plan to identify the individual farm upon which hogs reaching markets are produced has been developed in connection with the efforts toward eradicating tuberculosis among farm animals. While primarily intended as a means of tracing back to determine sources of disease infection, the system of tattooing which is being developed has other significant possibilities. With the growing emphasis on quality products in the market, it is only fair that the producers of high quality commodities receive the premiums paid by processors and consumers. Health of farm animals is a quality factor. The producer of healthy hogs should be rewarded. …


Ec28-36 Spraying Tree Fruits (Revised March 1932), C.C. Wiggans, E.H. Hoppert Jan 1928

Ec28-36 Spraying Tree Fruits (Revised March 1932), C.C. Wiggans, E.H. Hoppert

University of Nebraska-Lincoln Extension: Historical Materials

The production of sound, clean fruit is unquestionably one of the major problems facing the modern fruit grower. Culture may be neglected and pruning delayed for a time but the omission of sprays for even a single season demonstrates their absolute necessity. This applies equally to the commercial grower and to the farmer or gardener who has only a few trees.

Spray materials, equipment, management, schedules, insect pests and orchard diseases are discussed in this 1928 extension circular.


Rb28-229 Fattening Steers Of Various Ages, H.J. Gramlich Jan 1928

Rb28-229 Fattening Steers Of Various Ages, H.J. Gramlich

University of Nebraska-Lincoln Extension: Historical Materials

During recent years the beef industry has undergone vast changes. These have been made necessary in part by economic conditions and in part by changes in the demands of the American people. The tendency has been toward earlier marketing of steers, so that instead of going to the block as mature individuals at from 3 to 5 years of age, they are now reaching the market at a much younger age. In consuming centers where only heavy carcasses of beef were demanded formerly there is a call today for carcasses of the yearling and long yearling class.

The experiments reported …


A Research Delusion, George L. Peltier Jan 1928

A Research Delusion, George L. Peltier

Department of Plant Pathology: Faculty Publications

With the administrative heads of many of our educational institutions demanding a doctorate of every member of the permanent staff, as it is supposed to be a prerogative for research, and the issuing of a list of titles published each year by their staff, the urge for so-called research, namely, a list of titles, goes madly on. In fact publication sometimes becomes a sort of self-defense, for the absence of any titles over a brief period of years stamps one either as lacking the ability of doing research or inefficient. Likewise, such a policy has permeated the staff, so that …


Wild Birds Introduced Or Transplanted In North America, John C. Phillips Jan 1928

Wild Birds Introduced Or Transplanted In North America, John C. Phillips

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

The early history of the introduction of foreign birds into this country is mostly clothed in darkness. The records of many attempts, if such there were, have long since been buried in back numbers of local newspapers, and if any experiment was unsuccessful it was soon forgotten. Hence, one trying to get an accurate idea of what has happened soon realizes that he is following a hopeless quest. It is much the same with the transplanting of native birds, especially game birds, which have been carried about all over the country from west to east and from east to west …


The Structure And Development Of Corallobothrium With Descriptions Of Two New Fish Tapeworms (With Five Plates), Hiram Eli Essex Jan 1928

The Structure And Development Of Corallobothrium With Descriptions Of Two New Fish Tapeworms (With Five Plates), Hiram Eli Essex

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Introduction

Representatives of the genus Corallobothrium from American fish have never been described. Marshall and Gilbert (1905) report two members of this genus taken from Ameiurus melas (black bullhead) caught in the lakes at Madison, Wisconsin. La Rue (1914) refers to an undescribed species of Corallobothrium encysted in the livers of A. melas and A. nebulosus (common bullhead) from the Illinois River. Ward (1918) noted the presence of a species of Corallobothrium in lctalurus punctatus (channel-cat) at Milford, Nebraska. Aside from these incidental references, the American literature contains no information on this interesting group of fish tapeworms.

The acquaintance of …


Structure Of Texas Vegetation, J. E. Weaver Oct 1927

Structure Of Texas Vegetation, J. E. Weaver

Department of Agronomy and Horticulture: Faculty Publications

In his studies on the structure of the vegetation of eastern Texas, Tharp has recently made a notable contribution to plant ecology. That unexplored vegetation has always had an irresistible attraction for botanists is well ex-emplified in the resume of studies of Texas vegetation. An adequate review of the earlier work is given. This work began even before the colonists declared their independence from Mexico. It includes the studies of Lindheimer, who was both a geographer and collector; deals with the numerous papers along broad ecological lines by Bray; and traces the studies to the recent analysis of the vegetation …


Stem Rust In Nebraska. Part I. General Survey Of Sources. Part Ii. Identification Of The Physiologic Forms Of Puccinia Graminis From Various Sources, George L. Peltier, A. F. Thiel Jul 1927

Stem Rust In Nebraska. Part I. General Survey Of Sources. Part Ii. Identification Of The Physiologic Forms Of Puccinia Graminis From Various Sources, George L. Peltier, A. F. Thiel

Nebraska Agricultural Experiment Station: Historical Research Bulletins

Part I: Since the inception of the barberry eradication campaign in 1918 in Nebraska, the question has continually been asked, "Will the eradication of the barberry in the state eliminate or materially reduce stem rust?" In order that an answer might be obtained, an investigation to determine the sources of primary infection of stem rust on cereals was inaugurated in the spring of 1921. Although these studies have been carried on for 6 years, no definite statement regarding the relative importance of the primary sources and the amount of stem rust prevalent in the state from season to season originating …


Further Experiments With Poisoned Baits For Grasshoppers, M. H. Swenk May 1927

Further Experiments With Poisoned Baits For Grasshoppers, M. H. Swenk

Nebraska Agricultural Experiment Station: Historical Research Bulletins

In the summer of 1922 a series of experiments was carried on at the Scotts Bluff Experiment Substation for the purpose of finding, if possible, a formula for preparing an inexpensive and efficient poisoned bait for grasshoppers that could be recommended to the farmers of the North Platte valley, and also of learning more concerning the relative values of certain attractants and poisons commonly used in such baits, as well as the best time to scatter them to obtain the most satisfactory results. While the results were fairly conclusive from a qualitative standpoint, the time was not available in the …


The Pine Tipmoth In The Nebraska National Forest, M. H. Swenk Apr 1927

The Pine Tipmoth In The Nebraska National Forest, M. H. Swenk

Nebraska Agricultural Experiment Station: Historical Research Bulletins

On May 8, 1911, Mr. Smith Riley, the District Forester, with headquarters at Denver, in a letter to Acting Supervisor Pierce at Halsey, requested that the Nebraska Agricultural Experiment Station take up energetically the investigation of the pine tipmoth in the Nebraska National Forest. This request being presented to the Department by Mr. Pierce later in the month resulted in the presentation of the problem to the Experiment Station Council as a proposed Station project. The project was approved on May 31, 1911, and the expenses of the investigations of 1911 and 1912 that are reported upon in this bulletin …


Babcock Testing - Principles And Uses, L. K. Crowe, H. P. Davis Apr 1927

Babcock Testing - Principles And Uses, L. K. Crowe, H. P. Davis

Nebraska Agricultural Experiment Station: Historical Circulars

The manufacturing of dairy products on a commercial scale began about the middle of the nineteenth century and was greatly stimulated by the development of the centrifugal cream separator in the late eighties. The invention of the Babcock test in the early nineties overcame some of the difficulties that had developed in paying for milk upon its butterfat content, since it was early recognized that milk varied widely in that respect.


Crop Production In India, J. E. Weaver Apr 1927

Crop Production In India, J. E. Weaver

Department of Agronomy and Horticulture: Faculty Publications

It is rarely that one finds a book on the subject of agriculture of such broad scope, fascinating interest, and so full of the applications of ecology and physiology as Howard's " Crop-production in India." In every chapter numerous problems of plant growth in relation to environment are brought before the reader in such a stimulating manner that one can scarcely conclude but that ecology will reach its greatest usefulness in the field of general agriculture. It is a book to which every student of environment should have ready access.


Preliminary Notice Of A New Proboscidean Amebelodon Fricki, Gen. Et Sp. Nov., Erwin Hinckley Barbour Jan 1927

Preliminary Notice Of A New Proboscidean Amebelodon Fricki, Gen. Et Sp. Nov., Erwin Hinckley Barbour

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

Pursuant to advice from Mr. A. S. Keith of Freedom, Frontier County, Nebraska, the first Morrill Geological Expedition of the year was organized with Mr. Philip Orr in charge, and Mr. Keith's farm was visited at once, and on April 4th, 1927, the mandible, one rib, and a toe bone of a new proboscidean were procured.


Ec27-811 Harvesting Wheat In Nebraska With The Combined Harvester Thresher 1926, Arthur G. George Jan 1927

Ec27-811 Harvesting Wheat In Nebraska With The Combined Harvester Thresher 1926, Arthur G. George

University of Nebraska-Lincoln Extension: Historical Materials

Frequent inquiry from wheat growers in Nebraska and others as to the relative merits of the combined harvester-thresher as an efficienct and economical harvesting machine led the Nebraska Agricultural College to make a study of this problem in the summer of 1926. The work was carried on by the Departments of Rural Economics and Agricultural Engineering, cooperating with the United States Department of Agriculture which was conducting a similar survey in different parts of the United States. Perkins county, Nebraska, was the area selected for study as it is more or less typical of those parts of the state where …


A Revision Of The Nematodes Of The Leidy Collection, Arthur C. Walton Jan 1927

A Revision Of The Nematodes Of The Leidy Collection, Arthur C. Walton

Harold W. Manter Laboratory of Parasitology: Library Materials

Through the courtesy of Dr. Henry Baldwin Ward of the University of Illinois, and of Dr. J. Percy Moore of the University of Pennsylvania, the extensive nematode collection assembled by the late Joseph Leidy, and now housed in the museum of the University of Pennsylvania, has been made available for critical study and the present report is the first of a series covering this material. The writer wishes to express his hearty appreciation of the kindness of these two men, and also of that of Dr. Joseph Leidy, Jr., in making this opportunity possible. To make the study more complete …


Some Ecological Aspects Of Agriculture In The Prairie, J. E. Weaver Jan 1927

Some Ecological Aspects Of Agriculture In The Prairie, J. E. Weaver

Department of Agronomy and Horticulture: Faculty Publications

It is of more than passing interest that the cereal crops, namely: corn, spring and winter wheat, oats, barley, sorghum, and millet, have their center of greatest production in that portion of the United States originally covered by grassland. In fact, some are grown almost entirely in the grassland region, and other crops, as alfalfa and flax, which are similar in growth habits to wild legumes, wild flaxes, etc., growing among the grasses, also have their greatest acreage in grassland. Likewise, the largest areas of fruit production, including such tree fruits as apples, peaches, pears, and bush fruits as blackberries, …


The Immediate Effect Of Gametic Relationship And Of Parental Type Upon The Kernel Weight Of Corn, T. A. Kiesselbach Dec 1926

The Immediate Effect Of Gametic Relationship And Of Parental Type Upon The Kernel Weight Of Corn, T. A. Kiesselbach

Nebraska Agricultural Experiment Station: Historical Research Bulletins

This investigation to determine the relation of the kernel weight of corn to the source of pollen with which it was fertilized has been made to answer several questions of both practical and technical interest: (1) To what extent is kernel weight affected in the current crop by the "breadth of breeding" or the gametic relationship? (2) What is the relation of the diversity of parental type to the immediate effect of foreign pollen upon the kernel weight of corn? (3) Is the immediate effect of cross-fertilization upon the kernel weight of sufficient importance to justify the annual mixing of …


The Differential Reaction Of Strains Within A Variety Of Wheat To Physiologic Forms Of Puccinia Graminis Tritici, T. A. Kiesselbach, George L. Peltier Dec 1926

The Differential Reaction Of Strains Within A Variety Of Wheat To Physiologic Forms Of Puccinia Graminis Tritici, T. A. Kiesselbach, George L. Peltier

Nebraska Agricultural Experiment Station: Historical Research Bulletins

Black stem rust of wheat (Puccinia graminis tritici (Pers.) Erikss. & Henn.), which occurs in Nebraska and thruout most of the wheat producing regions of the world, is of a composite nature, in that it consists of a number of physiologic forms which can be determined by their action on different varieties of Triticum species, as shown by Stakman and Levine. The ordinary commercial variety of wheat may likewise be regarded as a mixture, in that it consists of numerous strains, which differ in some more or less important characteristics, as has been frequently indicated in the literature concerning …


Nutrient Requirements Of Growing Chicks, F. E. Mussehl Dec 1926

Nutrient Requirements Of Growing Chicks, F. E. Mussehl

Nebraska Agricultural Experiment Station: Historical Research Bulletins

The object of our experimental work was to establish if possible certain principles of poultry nutrition, permitting later a better combination of natural feedstuffs with the highest growth efficiency.


Alfalfa Investigations, T. A. Kiesselbach, Arthur Anderson Dec 1926

Alfalfa Investigations, T. A. Kiesselbach, Arthur Anderson

Nebraska Agricultural Experiment Station: Historical Research Bulletins

The purpose of these alfalfa investigations has been to determine the relation of variety, source of seed, and cultural practice to the yield and quality of hay produced. Due to the high initial cost of seeding, the inconvenience and wastefulness of losing a stand prematurely, and the superiority of properly-made hay, an understanding of these relationships is very important.


Studies On The Ascaris Lumbricoides, H. M. Martin Dec 1926

Studies On The Ascaris Lumbricoides, H. M. Martin

Nebraska Agricultural Experiment Station: Historical Research Bulletins

The Ascaris lumbricoides, in one phase or another, has attracted the attention of parasitologists for many years, and during the last decade this parasite has been studied by a large number of investigators. The recent observations have been, to a great extent, directed along one line, the study of its life history. These investigators have established two important points: (a) That the life history of Ascaris is more complex than was supposed, as it has been found that a vasculo-pulmonary circuit of the larvae is necessary before they settle down in the intestine, where they develop to the adult …


Studies On The Ascaris Lumbricoides, Harry Mathias Martin Dec 1926

Studies On The Ascaris Lumbricoides, Harry Mathias Martin

University of Nebraska-Lincoln Extension: Historical Materials

The Ascaris lumbricoides [roundworm], in one phase or another, has attracted the attention of parasitologists for many years, and during the last decade this parasite has been studied by a large number of investigators. The recent observations have been, to a great extent, directed along one line, the study of its life history. These investigators have established two important points: (a) That the life history of Ascaris is more complex than was supposed, as it has been found that a vasculo-pulmonary circuit of the larvae is necessary before they settle down in the intestine, where they develop to the adult …


The Segregation Of Carbohydrates In Crosses Between Waxy And Starchy Types Of Maize, T. A. Kiesselbach, N. F. Petersen Sep 1926

The Segregation Of Carbohydrates In Crosses Between Waxy And Starchy Types Of Maize, T. A. Kiesselbach, N. F. Petersen

Department of Agronomy and Horticulture: Faculty Publications

The purpose of this paper is to report the Mendelian segregation of waxy and starchy carbohydrates in both the sporophytic and gametophytic generations of maize. This is of especial genetic interest because the counts of segregate waxy kernels have very commonly been short of the expected numbers, although this character appears to be a simple Mendelian recessive. Collins (1909) was the first to point out the physical difference in the endosperm of waxy and ordinary starchy varieties.

While the exact difference in their chemical nature has not been established, Weatherwax (1922) considered that the waxy carbohydrate was erythrodextrin because of …


Turkey Production, F. E. Mussehl Jul 1926

Turkey Production, F. E. Mussehl

Nebraska Agricultural Experiment Station: Historical Circulars

Whatever problems turkey production presents, lack of demand for roast turkey is not at this time one of them. Turkeys rate so high in popular esteem that very rarely indeed do prices fall below that of dressed chickens and usually the best grades are 12 to 15 cents per pound higher during the holiday season. The world of commerce has become quite complex but the consuming public still has one clear way of speaking to producers. In the language of the dollar we are apparently being asked to raise more turkeys.


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.