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New Species And Collections Of Arrhenuri: 1921, Ruth Marshall Oct 1921

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 …


Localization Of The Motor Area In The Brain, Marian Josephine Xander Jun 1921

Localization Of The Motor Area In The Brain, Marian Josephine Xander

Biology Honors Papers

This 15 page thesis examines theories of brain function, localization of sense and motor area and experimental methods.


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.


The Regional Adaptation Of Corn In Nebraska, T. A. Kiesselbach, F. D. Keim Apr 1921

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 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.


Bulletin No 69 - The Poison Plants Of Western Australia, D. A. Herbert Jan 1921

Bulletin No 69 - The Poison Plants Of Western Australia, D. A. Herbert

Bulletins 1 - 2999

Up to the present no publication dealing with the whole of the known i)01S0fl plaits of Western Australia has been written. This Bulletin contains the collected accounts of various authors and correspondents which have been published at different times and contains a large amount of original information gathered both from field experience and from laboratory experiments. The work is not complete. A number of plants from distant districts have not been obtainable or obtainable only in amounts insufficient for exhaustive tests. These plants are comparatively few, however, and in Section 13 of this publication those which are suspected, but against …


Lignum-Vitae: A Study Of The Woods Of The Zygophyllaceae With Reference To The True Lignum-Vitae Of Commerce--Its Sources, Properties, Uses, And Substitutes, Samuel J. Record Jan 1921

Lignum-Vitae: A Study Of The Woods Of The Zygophyllaceae With Reference To The True Lignum-Vitae Of Commerce--Its Sources, Properties, Uses, And Substitutes, Samuel J. Record

Yale School of the Environment Bulletin Series

The true lignum-vitae of commerce belongs to the family Zygophyllaceae, of which only three genera, namely, Guaiacum, Porlieria, and Bulnesia, have representatives of tree size, and these are confined to the tropical and sub-tropical regions of the Western Hemisphere. Porlieria is of no commerical importance.


Heritable Characters Of Maize: Ix. Crinkly Leaf, R. A. Emerson Jan 1921

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 Jan 1921

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 …


Annual Report Of The Extension Division For The Year Ending June 30, 1920, C. Larsen, I. B. Johnson, W. F. Kumlien, W. W. Underwood, Harry J. Boyts, H. E. Dawes, Paul J. Scarbro, A. L. Haynes, Irene Dunne, Selma Rongstad, Geo H. Valentine, M. R. Benedict, J. C. Holmes, Ralph L. Patty, F. E. Mccall, G. S. Weaver, Manley Champlin, A. L. Ford Oct 1920

Annual Report Of The Extension Division For The Year Ending June 30, 1920, C. Larsen, I. B. Johnson, W. F. Kumlien, W. W. Underwood, Harry J. Boyts, H. E. Dawes, Paul J. Scarbro, A. L. Haynes, Irene Dunne, Selma Rongstad, Geo H. Valentine, M. R. Benedict, J. C. Holmes, Ralph L. Patty, F. E. Mccall, G. S. Weaver, Manley Champlin, A. L. Ford

SDSU Extension Circulars

The past year has been filled with unusual activity and interest along the different phases of agricultural extension work. The demand for the services of the different extension workers has greatly increased, so much so that it has become a problem as to how their time may be best assigned to accomplish the most.
Extension work is based upon cooperation. The counties, state, and government cooperate in finding the problems and in solving them. Some of these agricultural and rural problems may be solved in the local community; others need the assistance of the whole county; other problems, again, are …


Barberry Eradication, A. N. Hume, Henry C. Gilbert Apr 1920

Barberry Eradication, A. N. Hume, Henry C. Gilbert

SDSU Extension Circulars

The work of barberry eradication has been carried on for two years. This circular is a report on the work done, with notes on black stem rust. The work is cooperative between the United States Department of Agriculture, Office of Cereal Investigations, and the South Dakota State College Extension Division and Agronomy Department. The statements and figures given herein are for the state of South Dakota unless otherwise noted. They are well founded on accurate observations, experiments, or other sources of information. More detailed information will be given to those who desire it.


The Den: A Preliminary Report, With Map, Of A Tract Of Woodland Given To The School By Mr. And Mrs. Winthrop Perry., James W. Toumey, Ralph C. Hawley Mar 1920

The Den: A Preliminary Report, With Map, Of A Tract Of Woodland Given To The School By Mr. And Mrs. Winthrop Perry., James W. Toumey, Ralph C. Hawley

Yale School of the Environment Bulletin Series

In the autumn of 1918, through gift of Mr. and Mrs. Winthrop Perry, the School of Forestry came into possession of a number of closely connected parcels or woodland comprising over 1,300 acres in Farifield County Connecticut.

The purpose of the donors and conditions under which the gift was made are clearly stated....


Hymenoptera Collected Near Boston, Mass., With Descriptions Of A Variety Of Bombus Affinis, Joseph Bequaert Feb 1920

Hymenoptera Collected Near Boston, Mass., With Descriptions Of A Variety Of Bombus Affinis, Joseph Bequaert

Ba

While collecting Hymenoptera at Forest Hills, Mass., and other localities in the vicinity of Boston, I have taken on two occasions a bumble-bee, which from its aberrant coloration could not be properly named with Franklin's "Bombidae of the New World." I have been permitted to examine similarly colored Bombus, taken some years previous by Professor Wheeler at Forest Hills and by Mr. J. E. Smith at Sherborn, Mass. It was finally recognized that all these specimens belong to a striking color-variant of Bombus affinis, which it is the purpose of this note to describe and name. I have used this …


Ua94/6/1 Biology Notebook, Mildred Willian Jan 1920

Ua94/6/1 Biology Notebook, Mildred Willian

Student/Alumni Personal Papers

Biology notebook kept by Mildred Willian ca. 1920. Includes notes regarding different species and drawings.


Bulletin No 81 - The Improvement Of Pastures With Notes On The Pasture Trefoils In Western Australia, E. A. Mann, D. A. Herbert Jan 1920

Bulletin No 81 - The Improvement Of Pastures With Notes On The Pasture Trefoils In Western Australia, E. A. Mann, D. A. Herbert

Bulletins 1 - 2999

Agriculture can be roughly divided for practical purposes into two large divisions, those of animal husbandry and vegetable husbandry. It is with the former that this pamphlet is chiefly concerned and its object is to contribute, it possible, in some small measure towards the problem of how to increase time stock carrying capacity of our natural pasture lands. it is unnecessary to dwell upon the importance of this question, especially in relation to the remarkable developments which are taking place in time wool-growing industry in the Southern and more coastal areas of Western Australia.


Bulletin No 80 - Cultivation Of Sugar Beet, Percy G. Wicken Jan 1920

Bulletin No 80 - Cultivation Of Sugar Beet, Percy G. Wicken

Bulletins 1 - 2999

The beet belongs to the Chenopodiaceae or Salsolaceae, an order of plants which include among them many of the native saltbushes. The sugar beet (Beta vuigaris crassa) is supposed to have been developed from the wild beet (Beta vulgaris maritima), which is indigenous to the countries along the coast of Southern Europe. it is a biennial plant—that is, of two years' duration. The first year it produces a full-sized root, the second year it produces its seeds, and then dies off. Sometimes a few plants Produce seed the first year, but this is only on account of the seed being …


Heritable Characters Of Maize Ii.-Pistillate Flowered Maize Plants, R. A. Emerson Jan 1920

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 …


The Bees Of The Rocky Mountain National Park (Hymenop.), T. D. A. Cockerell Dec 1919

The Bees Of The Rocky Mountain National Park (Hymenop.), T. D. A. Cockerell

Co

No abstract provided.


Notes On North American Myxosporidia, Henry Baldwin Ward Dec 1919

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 Nov 1919

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 Sep 1919

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 …


Miscellaneous Notes On Hymenoptera With Descriptions Of New Genera And Species, John Colburn Bridwell Jun 1919

Miscellaneous Notes On Hymenoptera With Descriptions Of New Genera And Species, John Colburn Bridwell

Bo

No abstract provided.


Winthrop Davenport Foster [Obituary] Jun 1919

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 Jan 1919

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 …


Climate And Plant Growth In Certain Vegetative Associations, Arthur W. Sampson Oct 1918

Climate And Plant Growth In Certain Vegetative Associations, Arthur W. Sampson

Aspen Bibliography

The relation of climate to the growth and development of vegetation is of profound importance in both practical and experimental agriculture. It is extremely useful to know the cause of successful growth and establishment, or of partial success or failure, of various species in different plant associations and under widely contrasted climatic conditions. The climatic requirements of various plant types are largely responsible for the results obtained in the case of experimental seedings and plantings of most species. Once the adverse climatic factors are definitely known, failures with plants may be largely avoided by the judicious selection of sites or …


The Philippine Journal Of Science, T. D. A. Cockerell, Elizabeth Robinson, A. E. Wileman Jul 1918

The Philippine Journal Of Science, T. D. A. Cockerell, Elizabeth Robinson, A. E. Wileman

Co

No abstract provided.


Circular No. 29 - The Control Of Rodent Pests: Directions For Killing Ground Squirrels, Pocket Gophers, Rabbits, And Field Mice, Charles J. Sorenson Mar 1918

Circular No. 29 - The Control Of Rodent Pests: Directions For Killing Ground Squirrels, Pocket Gophers, Rabbits, And Field Mice, Charles J. Sorenson

UAES Circulars

Rodent pests cause heavy damage to the crops of Utah. The four most destructive of these pests are ground squirrels, pocket gophers, rabbits, and field mice.

The most effective method for the destruction of these animal pests is the use of poisoned baits. A very important factor in their control is the natural enemies.

The formulae recommended in the following pages have been, and are now being, used with excellent success in this and neighboring states.


The Story Of Aspen, Enos Mills Feb 1918

The Story Of Aspen, Enos Mills

Aspen Bibliography

No abstract provided.


Changing Diatoms Of Devils Lake, Clarence Elmore Feb 1918

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 Jan 1918

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 …