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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 …

Research Bulletin 22, Study Of The Environmental Conditions Influencing The Development Of Stem Rust In The Absence Of An Alternate Host, I 1922

University of Nebraska Historical Extension: Bulletin

Research Bulletin 22, Study of the Environmental Conditions Influencing the Development of Stem Rust in the Absence of an Alternate Host, I 1922

Research Bulletin 21, Studies Of Immunity Against Hemorrhagic Septicemia, 1922

University of Nebraska Historical Extension: Bulletin

Research Bulletin 21, Studies of Immunity Against Hemorrhagic Septicemia, 1922

Genetic Interrelations Of Two Andromonoecious Types Of Maize, Dwarf And Anther Ear, R. A. Emerson, Sterling H. Emerson

Department of Agronomy and Horticulture: Faculty Publications

Attention was called by Montgomery (1906)to the occasional appearance

of perfect flowers in the staminate inflorescence of maize and similar

cases were reported by Kempton (1913). Montgomery (1911) described

with illustrations a true-breeding type of semi-dwarf dent maize, the ears

of which were perfect-flowered. Perfect-flowered maize was described

and illustrated also by Blaringhem (1908, pp. 180-183). East and

Hayes (1911, pp. 13, 14) noted and illustrated a perfect-flowered sweet

corn. Weatherwax (1916, 1917) showed that typically pistillate

flowers of maize exhibit in microscopic sections the rudiments of stamens

and that staminate flowers show rudiments of pistils.

The Physiology Of The Respiration Of Fishes In Relation To The Hydrogen Ion Concentration Of The Medium, Edwin B. Powers

Papers in Systematics and Biological Diversity

Within recent years much has been added to the knowledge concerning the mechanism of the respiratory function of the blood. Haldane and Priestley (1905) have shown that, at least in the higher animals, the respiratory movements are affected by the carbon dioxide tension of the arterial blood. It has been shown definitely (Hasselbalch, 1912 and citations) that the exciting agent is the hydrogen ion concentration of the blood bathing the respiratory center.

Krogh and Leitch (1919) undertook to study the respiratory function of the blood of fishes in view of the knowledge of the influence of temperature upon the dissociation …

The Flat-Headed Apple-Tree Borer, Fred E. Brooks

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

The flat-headed apple-tree borer, a serious orchard pest throughout the greater part of United States, is found from the Atlantic to Pacific and from Florida and Texas to Canada.

The larva, or grub, of this insect (which in the adult stage is a medium-sized beetle) bores in the bark and wood of a great variety of trees, but is best known as an enemy of apple, pear, peach, and other cultivated fruit trees. Its depredations are felt in almost every locality where orchards have been planted.

Fortunately, this borer almost invariably confines its attacks to the sunny sides of trees …

New Species And Collections Of Arrhenuri: 1921, Ruth Marshall

School of Biological Sciences: Faculty Publications

The genus Arrhenurus, the largest group of the water mites, continues to yield new material from collections in lake regions. The new species described in this paper came from regions as far apart as Canada and China; while additional notes on already described species are based on material secured in several states of northeastern United States, some of them from new localities. Through the kindness of Professor N. Gist Gee, of Soochow University, material was secured for the description of new species from China. Professor Frank Smith and Dr. H. R. Vancleave, of the University of Illinois, were good enough …

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.

The Regional Adaptation Of Corn In Nebraska, T. A. Kiesselbach, F. D. Keim

Nebraska Agricultural Experiment Station: Historical Research Bulletins

The purpose of this investigation was to determine some of the factors involved in the regional adaptation of corn. The procedure has been to make a comparative study of native corn types, known to be locally adapted to various regional areas in Nebraska through long growth there. The work has been confined to the single species group - Zea mays indentata. No one variety of a common source is grown throughout the state, and therefore it has been impossible to keep within a single variety. It would appear that the data should indicate morphological and histological plant characteristics involved …

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.

Nebraska Test Special A: Shaw-Enochs Tractor Co. Shawnee Power Patrol, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

Heritable Characters Of Maize: Ix. Crinkly Leaf, R. A. Emerson

Department of Agronomy and Horticulture: Faculty Publications

In 1910 a strain of dent corn obtained at the National Corn Exposition held at Omaha was crossed with a strain of flint corn obtained from the Department of Agronomy of the University of Nebraska. The F₁ plants of this cross were normal and no abnormalities had been observed in the parent strains. But since the latter had not been subjected to self-pollination, there is no assurance that one or other of them did not have in it the character to be described here. In the F₂ generation of this cross there occurred a tpe of plant that …

The Relative Frequency Of Crossing Over In Microspore And In Megaspore Development In Maize, R. A. Emerson, C. B. Hutchison

Department of Agronomy and Horticulture: Faculty Publications

One of the early developments in the study of linkage in Drosophila was the discovery that the phenomenon of crossing over is confined to the female sex (Morgan 1912). The fact that no crossing over occurs in the male Drosophila holds true not only for sex-linked genes but for factors in the autosomes as well and is so well established that it affords a most convenient method of determining to which of the different linkage groups a new factor belongs.

The same phenomenon, but with the sexes reversed, obtains in the silkworm moth. Tanaka (1914, 1915) has found from back-cross …

Tractor Test 7: Case 20-40, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

Test ####: Withdrawn, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

Heritable Characters Of Maize Ii.-Pistillate Flowered Maize Plants, R. A. Emerson

Department of Agronomy and Horticulture: Faculty Publications

In the "freak"

class at the Annual

Corn Show held at Lincoln, Nebraska,

in the winter of 1913-14,

there was exhibited a corn tassel

with a heavy setting of seeds. A few

seeds are not infrequently found in the

staminate inflorescence of maize, particularly

in pod com, and tillers of various

corn varieties often end in ears instead

of in tassels or have tassels, the central

spikes of which are ear like. The freak

exhibited at the com show, however,

was a large. much branched affair.

wholly tassel-like in form except for the

fact that it bore a heavy crop …

Notes On North American Myxosporidia, Henry Baldwin Ward

Harold W. Manter Laboratory of Parasitology: Library Materials

In this paper are published data on three new species of Myxosporidia. Two species were observed in Lake Erie as parasites of a minnow; the third came from a species of Pacific salmon. Both cases present some unusual features that seem worthy of record.

Included are descriptions of Myxobolus aureatus nov. spec., Henneguya brachyura nov. sp., and Henneguya salminicola nov. spec.

I am greatly indebted to my colleague, Dr. Rokusaburo Kudo, for valuable assistance given while I was working up the material. The beautiful sketch illustrating the species from Lake Erie was prepared by Mrs. H. S. Jennings, to whom …

Fusarium Blight Of The Soy Bean And The Relation Of Various Factors To Infection, Richard O. Cromwell

Nebraska Agricultural Experiment Station: Historical Research Bulletins

An investigation was outlined (1) to determine the parasitism of Fusarium on soy bean, (2) to establish its relationship to Fusaria of the section Elegans in so far as a comparison of the cultural characters permitted, and (3) by means of cross- inoculations and field studies to determine the relationship of this disease of soy beans to the wilt disease of cowpeas (Vigna sinensis Hassk.) caused by Fusarium tracheiphilum Smith. The results of these investigations up to the close of the summer of 1916 have been reported. The studies were continued at the North Carolina Experiment Station until the …

On The Specific Identity Of Heronimus Chelydrae Maccallum And Aorchis Extensus Barker And Parsons, Horace Wesley Stunkard

Harold W. Manter Laboratory of Parasitology: Library Materials

The monostomes are among the least known of North American trematode groups. Records give descriptions of only six species, each the single representative of a genus, and according to the classification of Ward (1918) belonging to four different families. Existing descriptions in most cases are far from complete and data necessary for taxonomic determination are lacking. This deficiency has been pointed out by other workers, both in this country and in Europe, and the classification of the monostomes is not well established. In fact, certain investigators regard them as aberrant forms, sprung from different distome groups, which alike have lost …

Winthrop Davenport Foster [Obituary]

Harold W. Manter Laboratory of Parasitology: Library Materials

December 28, 1880, Jersey City, New Jersey, USA - October 6, 1918, Washington, DC, USA. Cause of death: Pneumonia, as a complication of influenza.

Winthrop Davenport Foster's work in parasitology was done principally on the parasites of swine and along the lines of critical tests of the efficacy of anthelmintics, though he published a number of notes on other lines.

The Ecological Relations Of Roots, John E. Weaver

Papers of John E. Weaver (1884–1956)

Although considerable progress has been made in the study of root systems of desert plants (Cannon, 1911, 1913; Markle, 1917), very little information is available concerning the roots of other native species. During 1914 the writer investigated the root systems of the prairie plants of southeastern Washington, where the annual precipitation is only 21.6 inches and occurs mostly in the period of rest: Since that time it has been planned to make a comparative study of the roots of prairie plants growing in a more humid region and where the precipitation occurs mostly during the season of plant growth. The …

Research Bulletin 14, Fusarium Blight Of The Soy Bean And The Relation Of Various Factors To Infection, 1919

University of Nebraska Historical Extension: Bulletin

Research Bulletin 14, Fusarium Blight of the Soy Bean and the Relation of Various Factors to Infection, 1919

On A New Subspecies Of Otter From Nebraska, Myron Harmon Swenk

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

Formerly otters were very common along all of our Nebraska streams. In the winter of 1819-20 they were found frequently on the Missouri river and tributary streams near Engineer Cantonment (north of Omaha), as reported by Edwin James, that botanist and geologist of the Major S.H. Long Expedition. At Fort Kearny, Nebraska, on July 5, 1856, W.S. Wood with Lieut. F.T. Bryan's survey party obtained a young female otter which is now Cat. No. 1877 (skin) and 2575 (skull) of the U.S. National Museum. Otters were also extensively and persistently trapped by the early trappers and Indians, and due to …

Changing Diatoms Of Devils Lake, Clarence Elmore

School of Biological Sciences: Faculty Publications

During the summer of 1915 I spent some time at the Biological Station of the University of North Dakota at Devils Lake, investigating the diatoms of the lake. Before this considerable diatom material had been sent to me by Dr. R. T. Young of the University, who is conducting the biological survey of the lake.
The immediate practical object in the survey is to determine the organisms in the lake in relation to the fish that might be able to subsist upon them, and diatoms being the most abundant of microscopic plants, deserve special attention in this connection. At present …

Further Studies In The Ecotone Between Prairie And Woodland, R. J. Pool, J. E. Weaver, F. C. Jean

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

A series of intensive investigations of the ecological features of the tension zone between prairie and woodland in the Mississippi valley was begun by Weaver and Thiel in 1915. These studies were continued for two seasons in Minnesota and were also extended to the prairies of eastern Nebraska in 1916. These investigations represent the first attempt to attack the prairie-forest problem on a comprehensive scale by means of the quantitative methods of modern ecology. Some of the results secured from these studies have been published as the first paper of a series planned to deal with critical investigations in the …

On A New Species Of Otter From Nebraska, Myron Harmon Swenk

University of Nebraska State Museum: Mammalogy Papers

In 1908 I referred our Nebraska otters to L. c. sonora (Rhoads), basing this conclusion on the mounted specimen in the University Museum, because of its large size and pallor, that being the only Nebraska specimen in any collection in the state at that time, and, so far as known to me, the only Nebraska specimen extant except the young female in the U. S. National Museum mentioned above. In 1915 I repeated this identification. The taking of a fine old male otter with a perfect skull in eastern Nebraska in 1916 reopened the whole question, and a close study …

Relation Of Size Of Seed And Sprout Value To The Yield Of Small Grain Crops, T. A. Kiesselbach, C. A. Helm

Nebraska Agricultural Experiment Station: Historical Research Bulletins

A superior yielding power has frequently been attributed to the extra large seed. Since the seeds of any given crop commonly differ markedly in size, it is of importance from the standpoint of crop production to know the extent to which this difference in size may affect the yield of the crop produced. The following experiments have been conducted for the purpose of contributing further to the information upon this subject.

On The Structure And Classification Of North American Parasitic Worms, Henry Baldwin Ward

Harold W. Manter Laboratory of Parasitology: Library Materials

For many years I have been engaged in the study of parasitic worms from North American freshwater hosts, mostly fish; during this time I have had opportunity to examine and compare material from a large number of localities embracing many widely separated points. In this work I have been aided very greatly by studies on individual groups undertaken and published under my direction by various graduate students to whom my obligation is freely expressed here. In connection with this work it has been necessary to examine critically all original records of parasites from similar hosts and to endeavor to reach …

Color And Color-Pattern Mechanism Of Tiger Beetles, Victor E. Shelford

University of Nebraska State Museum: Entomology Papers

In 1903 the writer undertook a study of variation of the tiger beetles. The work here presented is the outgrowth of this beginning, and indeed includes some small portions regarding color patterns that were written in that year. The work has been prolonged for many reasons, but chief of these was the very large number of species in the group and the fact that an adequate understanding of the material could not be attained without consulting many large collections. Further, the experimental results obtained in 1906 demanded a firsthand study of the variations of the species concerned and their natural …

Genetical Studies Of Variegated Pericarp In Maize, R. A. Emerson

Department of Agronomy and Horticulture: Faculty Publications

Two years ago there were presented some results of a study of the inheritance of self pattern in the pericarp of maize seeds, occurring as a sporophytic2 variation in variegated ears (EMERSON1 914). Further results, in entire accord with those previously reported, have now been obtained. In addition, data bearing upon new phases of the problem are also available.

The chief results reported in the earlier paper were the following: ( I ) The more nearly self-colored the pericarp of any seed of a variegated ear, the more likely is the progeny of that seed to produce a self-colored ear …