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The Intrusions Of Science, S. B. Gass Jan 1913

The Intrusions Of Science, S. B. Gass

Mid-West Quarterly (1913–1918)

It is not infrequently related that human arrogance was sadly but not unjustly rebuked by Darwin and the evolutionary science of the Nineteenth Century. And indeed from the point of view of pure science there was arrogance in an assumption that the enveloping intelligence of the universe looked upon mankind as its terminus ad quem to which all parts were subordinate--in an assumption that men were made in the likeness of an over-ruling power that worked by ways which, paradoxically, even that likeness was fain to call mysterious and incomprehensible. Science seemed to make these ways less mysterious, less incomprehensible; …


Shorter Articles And Discussion Simplified Mendelian Formulae, R. A. Emerson Jan 1913

Shorter Articles And Discussion Simplified Mendelian Formulae, R. A. Emerson

Department of Agronomy and Horticulture: Faculty Publications

I was somewhat surprised by 'Morgan's and Castle's suggestions for a simplification of Mendelian formulae. My surprise was not occasioned so much by the forms these suggestions took as by the fact that any pronounced changes were deemed necessary. I had not only employed the usual formula in my own work but had found no difficulty worth mentioning in understanding the formula used by most other workers in Mendelian fields. My experience with students in elementary courses in genetics had not prepared me for the idea that such formula were particularly difficult. Nevertheless I believe in simplifying the formulae if …


The Possible Origin Of Mutations In Somatic Cells, R. A. Emerson Jan 1913

The Possible Origin Of Mutations In Somatic Cells, R. A. Emerson

Department of Agronomy and Horticulture: Faculty Publications

That mutations are accompanied by some change in the germ-plasm is, I take it, indisputable. Have we, however, any reason to suppose that the change takes place within the germ cells? I am not sure, as a matter of fact, that genetists in general regard the gametes as the place of origin of mutations. It is true, however, that experiments in the artificial production of mutations in plants have been limited largely to treatments of the ovaries from about the time of the reduction division to about the time of fertilization. This suggests a belief on the part of investigators …


Shorter Articles And Reports: The Simultaneous Modification Of Distinct Mendelian Factors, R. A. Emerson Jan 1913

Shorter Articles And Reports: The Simultaneous Modification Of Distinct Mendelian Factors, R. A. Emerson

Department of Agronomy and Horticulture: Faculty Publications

In another paper on the inheritance of a recurring somatic variation in variegated ears of maize, it was shown that the amount of red color developed in the pericarp of variegated seeds bears a definite relation to the development of color in the progeny of such seeds. The relation is such that the more color there is in the pericarp of the seeds planted the more likely are they to produce plants with wholly self-red ears and correspondingly the less likely to produce plants with variegated ears. Self-red ears thus produced behave just as if they were hybrids between self-red …


Some Of The Next Steps In Botanical Science, Charles E. Bessey Jan 1913

Some Of The Next Steps In Botanical Science, Charles E. Bessey

School of Biological Sciences: Faculty Publications

When one who has worked long in any

field of science speaks before an audience

such as this he is expected to say something

about the condition of his branch of science

when he began work with meager and

poorly adapted apparatus, to contrast it

with its greatly improved condition to-day,

and to dwell with pride upon the finely

equipped laboratories with costly apparatus

especially designed for particular

experiments, to be found by the twentieth

century scientific student. And 1 must

confess that the temptation to do so was

one difficult to resist, for we who have

grown old in …


Some American Lebertia, Ruth Marshall Oct 1912

Some American Lebertia, Ruth Marshall

School of Biological Sciences: Faculty Publications

The genus Lebertia of the water-mites is easily recognized by the character of the epimera. It belongs to a small group of genera, the subfamily Lebertiinae, characterized by the union of the four pairs of epimera into a single group, with their more or less complete fusion. This forms a shield which covers a large part of the ventral surface of the body.


The Unexpected Occurrence Of Aleurone Colors In F2 Of A Cross Between Non-Colored Varieties Of Maize, R. A. Emerson Jan 1912

The Unexpected Occurrence Of Aleurone Colors In F2 Of A Cross Between Non-Colored Varieties Of Maize, R. A. Emerson

Department of Agronomy and Horticulture: Faculty Publications

Before the Mendelian methods of analysis became available, considerable wonder would doubtless have been excited by the "mysterious" appearance in F2 of one colored grain-purple or red-to every five or six white ones in case of a maize cross, both parents and F, of which had only white grains. An occurrence of this sort has recently been noted in one of my maize cultures and the F2 numbers are explained here as a trihybrid or tetrahybrid ratio. The crosses in question were made primarily for a study of size inheritance and fairly large numbers have been grown. The varieties …


A Consideration Of The Physiology And Life History Of A Parasitic Botrytis On Pepper And Lettuce, George L. Peltier Jan 1912

A Consideration Of The Physiology And Life History Of A Parasitic Botrytis On Pepper And Lettuce, George L. Peltier

Department of Plant Pathology: Faculty Publications

During the autumn of 1911, while gathering the peppers (Capsicum) in the vegetable plat of the Missouri Botanical Garden, the writer observed a fungus which was appearing as a parasite on the fruits. The peduncles were covered with a dark brown mass of conidia and mycelium, which so weakened the tissues that the fruit soon fell to the ground. On opening the peppers a number of large, flat, crust-like sclerotia, 1 cm. long and .5 cm. wide, were found to fill the interior. In most cases the seeds were also covered with the crust-like masses. The conidial stage …


The Present Methods Of Teaching Entomology, J. H. Comstock Feb 1911

The Present Methods Of Teaching Entomology, J. H. Comstock

Department of Entomology: Faculty Publications

The present methods of teaching entomology followed in the United States have been developed almost entirely by men now teaching this subject. A second generation of teachers has begun its work; but the first is still on the stage. We h3i¥e progressed far enough, however, to make it worth while for the teachers to compare methods, in order that each may profit by the experience of the others. In a conference of this kind the contribution of each to the discussion will be, naturally, at first, merely a statement of the methods evolved in our several widely separated institutions. Then …


Present Methods Of Teaching Entomology At The University Of Nebraska, Lawrence Bruner Jan 1911

Present Methods Of Teaching Entomology At The University Of Nebraska, Lawrence Bruner

Department of Entomology: Faculty Publications

'When our Secretary sent out his preliminary notification of this meeting and asked me to take part in a discussion of "present methods of teaching Entomology," the matter at first seemed of little importance so far, at least, as the speaker was concerned. However, after giving the subject some thought I have decided that it might be well at least to take the time and trouble to attempt to explain briefly a few of the methods by which the student in Nebraska is enabled to absorb some entomological information. In order to do this with an unbiased feeling it might …


Discussion And Correspondence Coupling Vs. Random Segregation, R. A. Emerson Jan 1911

Discussion And Correspondence Coupling Vs. Random Segregation, R. A. Emerson

Department of Agronomy and Horticulture: Faculty Publications

To the editor of science: The suggestion offered by Morgan, in SCIENCE of September 22, to account for the coupling and repulsion of factors for various characters in inheritance in such forms as Abraxas, Drosophila, fowls, sweet peas, etc., incites this note.

Briefly Morgan's hypothesis is (1) that the materials representing factors that couple are "near together in a linear series" in the chromosomes; (2) that, when pairs of parental chromosomes conjugate, "like regions stand opposed "; (3) that "homologous chromosomes twist around each other," but that the separation of chromosomes is in a single "plane"; (4) that, thereby the …


Botanical Teaching, Charles E. Bessey Jan 1911

Botanical Teaching, Charles E. Bessey

School of Biological Sciences: Faculty Publications

Some months ago a suggestion was made that at this dinner we should ask ourselves the question: Why is it that with the enormous classes we are having in botany there is a marked dearth of properly trained men who can serve as instructors in colleges and universities?


New Elementary Agriculture, Charles E. Bessey, Lawrence Bruner, Goodwin D. Swezey Jan 1911

New Elementary Agriculture, Charles E. Bessey, Lawrence Bruner, Goodwin D. Swezey

School of Biological Sciences: Faculty Publications

This is an agricultural nation. The products of the soil are the basis of her industries and her prosperity. The children of our great Commonwealths should be familiar with our crops, our grains and grasses, our flowers and fruits, our trees and shrubs and weeds, our domestic animals and birds and insects. Our children should have a practical knowledge of the management of a farm, of the composition of the soil, and of the adaptability of the farm and its soil for the cultivation of certain plants and the counter effect of such plant growth upon the soil. They should …


New Studies Of The Arrhenuri, Ruth Marshall Dec 1910

New Studies Of The Arrhenuri, Ruth Marshall

School of Biological Sciences: Faculty Publications

Since the publication of "The Arrhenuri of the United States," in 198, the author has been fortunate enough to secure enough more material to justify the publication of a supplementary paper on this large genus of water-mites. This material consists of collections from new localities in the United States, and of additional material from old collecting grounds, together with a few specimens from other countries. The author's own collections were made in Wisconsin and Illinois. A few new places were visited, as the lakes about Milwaukee ; and more extensive collections were made in previously known bodies of water, as …


The Inheritance Of Sizes And Shapes In Plants, R. A. Emerson Jan 1910

The Inheritance Of Sizes And Shapes In Plants, R. A. Emerson

Department of Agronomy and Horticulture: Faculty Publications

Some years ago Lock reported a cross of a tall race of maize with a shorter race which produced an intermediate height in F1 and exhibited no segregation in F2 when crossed back with one of the parents. Castle's results with rabbits are very similar to those of Lock with maize. Castle summarizes his results in part as follows:

A cross between rabbits differing in ear-length produces offspring with ears of intermediate length, varying about the mean of the parental ear-lengths. . . . A study of the offspring of the primary cross-breds shows the blend of the …


Bulletin 111, Changes In The Composition Of The Loess Soils Of Nebraska Caused By Cultivation, 1909 Jan 1909

Bulletin 111, Changes In The Composition Of The Loess Soils Of Nebraska Caused By Cultivation, 1909

University of Nebraska Historical Extension: Bulletin

Bulletin 111, Changes in the Composition of the Loess Soils of Nebraska Caused by Cultivation, 1909


The Arrhenuri Of The United States, Ruth Marshall Sep 1908

The Arrhenuri Of The United States, Ruth Marshall

School of Biological Sciences: Faculty Publications

The Arrhenuri comprise the largest genus of the Hydrachnidz, and one of the most highly differentiated and widely distributed. The genus is easily recognized by the following characters. The thick chitinous covering of the body is pierced by large pores. A circular furrow on the dorsal side marks off an area which is entirely enclosed in the female, in the male usually open onto the posterior extension of the body. The females are oval in form and much alike ; the males are smaller and vary greatly from each other and from the females. They are characterized by a posterior …


Press Bulletin 29, Pocket Gophers, 1908 Jan 1908

Press Bulletin 29, Pocket Gophers, 1908

University of Nebraska Historical Extension: Bulletin

Press Bulletin 29, Pocket Gophers, 1908


Revision Of The Non-Combed Eyed Siphonaptera, Karl Jordan, Nathaniel Charles Rothschild Jan 1908

Revision Of The Non-Combed Eyed Siphonaptera, Karl Jordan, Nathaniel Charles Rothschild

Harold W. Manter Laboratory of Parasitology: Library Materials

Introduction (excerpt)

The importance of certain species of fleas in relation to the epidemiology of plague has been so amply demonstrated (see Journal of Hygiene, volumes VI 1906, p. 426, and VII 1907, p. 395) that an explanation appears scarcely necessary for our publishing a paper dealing with a revision of the non-pectinated eyed Siphonaptera. With the demonstration that fleas are capable of transmitting plague, their study at once ceased to be the mere hobby of a small group of entomological specialists. An accurate knowledge of fleas, both with regard to their structure and biology, is at present a …


The Arrhenuri Of The United States, Ruth Marshall Jan 1908

The Arrhenuri Of The United States, Ruth Marshall

Harold W. Manter Laboratory of Parasitology: Faculty Publications

The Arrhenuri comprise the largest genus of the Hydrachnidre, and one of the most highly differentiated and widely distributed. The genus is easily recognized by the following characters. The thick chitinous covering of the body is pierced by large pores. A circular furrow on the dorsal side marks off an area which is entirely enclosed in the female, in the male usually open onto the posterior extension of the body. The females are oval in form and much alike; the males are smaller and vary greatly from each other and from the females. They are characterized by a posterior prolongation …


Bulletin 103, Mite Accompanying The Bud-Rot Of Carnations, 1907 Jan 1907

Bulletin 103, Mite Accompanying The Bud-Rot Of Carnations, 1907

University of Nebraska Historical Extension: Bulletin

Bulletin 103, Mite Accompanying the Bud-rot of Carnations, 1907


On The Movements Of Petals, Esther Pearl Hensel Jul 1905

On The Movements Of Petals, Esther Pearl Hensel

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

The following paper has to do with an investigation of the physical causes· which bring about opening and closing movements, periodic or otherwise, of certain flowers. With that end in view, seven different species of flowering plants have been experimented upon directly, a much larger number being simply observed with respect to the nature, time, etc., of their anthotropic movements. Movement consists in the corolla taking upon itself either the open or closed position for certain periods of the day or night; for example, the morning glory (Ipomoea purpurea) opens early in the morning (from 4:00 to 5 …


Plant Migration Studies, Charles E. Bessey Jan 1905

Plant Migration Studies, Charles E. Bessey

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

It is a familiar fact that new species appear from time to time among the native plants of a region. Such newcomers turn out on examination to be new only in the sense that they have not previously lived in the region, and in every instance these new plants are found to have come from other regions where they had existed for a longer or shorter period of time. In some cases the new species remain for a time and then disappear, or at least become inconspicuous, but more commonly they crowd in among the former plants and become permanent …


Electric Double-Refraction In Carbon Disulphide At Low Potentials, Gustaf W. Elmen Jan 1905

Electric Double-Refraction In Carbon Disulphide At Low Potentials, Gustaf W. Elmen

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

When light polarized at an angle of forty-five degrees to the; lines of force is passed through certain dielectrics, between two parallel electrodes, they become double-refracting. The difference of phase, 0, between the two components of light at right angles and parallel to the lines of force, as represented by Kerr and verified by later investigators, is

8=+_BP2l

a2

where B is the electro-optic constant, depending on the dielectric, l the length, and a the distance between the plate electrodes in centimeters, and P the difference of potential between the electrodes in e.G.S. units.

From data obtained …


Plant Migration Studies: Forest Trees, Charles E. Bessey Jan 1905

Plant Migration Studies: Forest Trees, Charles E. Bessey

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

It is a familiar fact that new species appear from time to time among the native plants of a region. Such newcomers turn out on examination to be new only in the sense that they have not previously lived in the region, and in every instance these new plants are found to have come from other regions where they had existed for a longer or shorter period of time. In some cases the · new species remain for a time and then disappear, or at least become inconspicuous, but more commonly they crowd in among the former plants and become …


The Relation Of Leaf Structure To Physical Factors, Edith Schwartz Clements Jan 1905

The Relation Of Leaf Structure To Physical Factors, Edith Schwartz Clements

School of Biological Sciences: Faculty Publications

The leaf, as the seat of important physiological functions of the plant, and because of its modification by external factors, has long been a fruitful subject for investigation. As a rule, however, investigators have confined themselves solely to the histology and morphology of the leaf, independent of its relations to physical factors. Where the latter have been considered at all, it has been in a more or less general way, or undue importance has been assigned to one or another of the physical factors, and others have been ignored entirely. In no case have they been carefully measured. The aim …


The Grasses Of Nebraska, Charles E. Bessey, Robert Bolin , Depositor Jan 1905

The Grasses Of Nebraska, Charles E. Bessey, Robert Bolin , Depositor

School of Biological Sciences: Faculty Publications

Dr Bessey was the Nebraska State Botanist and Professor of Botany at University of Nebraska. This report contains a classification list of grasses found in the state and brief comments on the usefulness of the various grasses.


The Distribution Of The Native Forest Trees Of Nebraska, Charles E. Bessey, Robert Bolin , Depositor Jan 1904

The Distribution Of The Native Forest Trees Of Nebraska, Charles E. Bessey, Robert Bolin , Depositor

School of Biological Sciences: Faculty Publications

This document lists 67 trees identified by Dr Bessey with the help of others around the state. It includes the common and scientific names as well brief comment about each tree. Small maps are provided showing the distribution of each tree.


A Preliminary Review Of The Birds Of Nebraska With Synopses, Lawrence Bruner, Robert H. Wolcott, Myron H. Swenk Jan 1903

A Preliminary Review Of The Birds Of Nebraska With Synopses, Lawrence Bruner, Robert H. Wolcott, Myron H. Swenk

Papers in Ornithology

In 1896, Prof. Bruner published his list entitled "Some Notes on Nebraska Birds." As a working basis for the study of the ornithology of the state it has proven invaluable and it has also been greatly in demand by people not ornithologists, who desired to "know something about our birds." That edition was exhausted some time ago and its author has been frequently urged to publish another. However, the organization of the Nebraska Ornithologists' Union and the development of ornithology in the University has led to such a rapid increase in our knowledge in the past five years that it …


Report On The Work Of The Morrill Geological Expeditions Of The University Of Nebraska, Carrie Adeline Barbour Jun 1900

Report On The Work Of The Morrill Geological Expeditions Of The University Of Nebraska, Carrie Adeline Barbour

Department of Earth and Atmospheric Sciences: Faculty Publications

Through the generosity of the Hon. Charles H. Morrill, of Lincoln, the expeditions sent out from the University of Nebraska, known as the Morrill Geological Expeditions, have become a permanent organization of the University. Therefore, it is but a fitting mark of respect that reports of these expeditions be given to the Nebraska Academy of Science from time to time in order that they may become matters of record. Introductory to this work, a private geological excursion was undertaken in June of 1891, by Mr. Erwin Hinckley Barbour in the interest of the University of Nebraska. At this time the …