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Full-Text Articles in Life Sciences

The North American Species Of Smilacina, Desma H. Galway May 1945

The North American Species Of Smilacina, Desma H. Galway

Theses and Dissertations

This paper is the result of a taxonomic study of the species of the genus Smilacina occurring naturally in North America north of Mexico. In the past it has been difficult to make satisfactory determinations of members of this genus from existing manuals, especially among western forms. West of the great plains the great diversity in environmental conditions has given rise to a diversity in form of the species that are widely distributed. Many of these forms have been given specific or varietal names recently, and as no comprehensive work on the genus has been done since most of these …


The Influence Of Some Alkali Salts In The Presence Of Various Concentrations Of Calcium On The Growth Of Sporobolus Cryptandrus, Vaughn A. Clayton May 1942

The Influence Of Some Alkali Salts In The Presence Of Various Concentrations Of Calcium On The Growth Of Sporobolus Cryptandrus, Vaughn A. Clayton

Theses and Dissertations

This study deals with the reactions of Sporobolus cryptandrus to various concentrations of Utah's most common alkali salts. Its purpose is to determine the effects of various concentrations of sodium chloride, sodium carbonate, and sodium sulphate on the growth and fruiting of Sporobolus cryptandrus, and to determine to what extent, if any, various levels of calcium exert a protective influence against the toxicity of these three salts. In addition to the experimental work a field of study was conducted for the purpose of determining the concentrations of total salts found in soils supporting a good growth of Sporobolus cryptandrus.


Study Of The Aquatic And Semiaquatic Coleoptera In The State Of Utah, Harry P. Chandler May 1941

Study Of The Aquatic And Semiaquatic Coleoptera In The State Of Utah, Harry P. Chandler

Theses and Dissertations

The purpose of this paper is to discover and make known the species of aquatic and semiaquatic Coleopters of the sub-order ADEPHAGA which occur in Utah and to give something of their distribution, environment and habits whenever possible. When ever possible the original description or a description from a recent revision has been included for each species. Descriptions given in recent revisions have been regarded as more desirable because they describe the species in comparison with its nearest relatives, while many fo the original descriptions were very incomplete and could not be used to separate many of our present species …


The Distribution Of Plant Types In The Escalante Desert Of Utah With Relation To Soil Conditions, Carlyle B. Lambert May 1940

The Distribution Of Plant Types In The Escalante Desert Of Utah With Relation To Soil Conditions, Carlyle B. Lambert

Theses and Dissertations

This problem was a study of plant species in the Escalante Desert, Utah, in relation to soil conditions. The plants were surveyed by the transect-plot method. The plants and soils were analyzed by percentage-frequency techniques. There is no measurable correlation between soil series and the dominant plants which occur on the soils. There is no correlation between soil types and the plants that are dominant on the soil types. There is a definite correlation between textural classes of the soil and the plants that are dominant on these classes.


The Rise And Development Of The Megagametophyte In Yucca Angustissima Engelmann, Antone W. Nisson May 1939

The Rise And Development Of The Megagametophyte In Yucca Angustissima Engelmann, Antone W. Nisson

Theses and Dissertations

The studies involved in this investigation are based upon data and materials secured in the sandy areas of Washington and Iron Counties in southern Utah. The regions in which Yucca angustissima is found have a scant vegetation, are dry, sandy to sandy loam, well-drained, and with an elevation of from 2500 to 5000 feet. Watkins (1937) worked out a very extensive report of the megagametophyte development of Yucca rupicola. He begins with the four megaspore stage, and shows next the disintegration of the three micropylar megaspores. He reported that the chalazal megaspore forms eight free nuclei, by three successive divisions, …


A Preliminary Study Of The Vegetative Cover In Spanish Fork Canyon, Utah, Ben S. Markham Jan 1939

A Preliminary Study Of The Vegetative Cover In Spanish Fork Canyon, Utah, Ben S. Markham

Theses and Dissertations

Spanish Fork Canyon is located in central Utah and is part of the Wasatch Mountain range. Since the coming of the white man to this section of country it has been used as a trail. The canyon provides summer range for stock as well as a watershed. Plant densities were determined by the point observation method using series of one-hundred square foot plots. Three areas which have been subject to different grazing uses were studied. The association changes in the canyon are the replacement of sage by slender wheatgrass on the shallow soils and the disclimax condition resulting from over-grazing …


The Influence Of Overgrazing On The Density And Number Of Palatable And Unpalatable Desert Forage Plants, John H. Mcguire Jan 1937

The Influence Of Overgrazing On The Density And Number Of Palatable And Unpalatable Desert Forage Plants, John H. Mcguire

Theses and Dissertations

The data for this problem were collected at the Desert Range Experiment Station and on adjoining public domain lands during the summer of 1934, for the purpose of studying the influence of overgrazing on the increase of palatable and unpalatable desert forage plants. A vegetative description of the two areas studied has been prepared and presented.


A Further Study Of Utah Asilidae, D. Elmer Johnson May 1936

A Further Study Of Utah Asilidae, D. Elmer Johnson

Theses and Dissertations

This study is based on a similar study made by Claudeous J. D. Brown in 1928, and published in 1929. The species he used have been rechecked, and additional ones have been studied. The species considered in this study represent three of the four subfamilies of North American Asilidae. These three subfamilies are Dasypogoninae, Laphriinae, and Asilinae. This study is limited to those species in the Brigham Young University Collections, and to species recorded in print. No claim is here made that all the forms inhabiting the state have been discovered, in fact the writer is well aware of the …


The Development Of The Embryo Of Iris Missouriensis Nutt, C. Eugene Larsen May 1936

The Development Of The Embryo Of Iris Missouriensis Nutt, C. Eugene Larsen

Theses and Dissertations

There is but a single species of Iris native to Utah. This is Iris missouriensis Nutt. This plant was chosen for investigation because of its possible significance and because material of this species was readily available. The embryo of Iris missouriensis Nutt. shows some resemblance to the Lily type in its development of an irregular dividing suspensor. It also resembles the Orchid type in the usual development of sixteen cells before the dermatogen is cut off. In general development, however, the writer believes it to have an embryo sequence more similar to the Alisma type than to the dexcriptions given …


A Taxonomical, Morphological And Distributional Study Of The Utah Cyprinidae /|Cby Sheldon Phipps Hayes, Sheldon Phipps Hayes May 1935

A Taxonomical, Morphological And Distributional Study Of The Utah Cyprinidae /|Cby Sheldon Phipps Hayes, Sheldon Phipps Hayes

Theses and Dissertations

The hydrography of Utah may be thought of as being roughly divided into two large general drainage areas--, the Colorado River draining the eastern halt and southern portion ot the state and the Bonneville Drainage encompassing the remaining part of it. Earlier workers have listed eight genera and fourteen species of minnows occuring in Utah. Of these this report includes seven genera and ten species found within the borders of our state.


Effects Of Overgrazing On The Mortality Of Desert Browse Of The Utah West Desert, Charles W. Menzies Jan 1935

Effects Of Overgrazing On The Mortality Of Desert Browse Of The Utah West Desert, Charles W. Menzies

Theses and Dissertations

During the summer of 1934 this investigation was conducted to determine the effect of overgrazing on the mortality of desert browse in the vicinity of the Desert Range Branch experiment station. Range lands of western United States have, as a whole been subjected to overgrazing. Utah has about 24 million acres of public acres of public domain that can only be utilized from grazing. An effort has been made to put this area under control. The "Taylor Grazing Act" passed by Congress June 28, 1934 is a big step in the direction of the control of this vast area of …


A Study Of The Plant Ecology Of Salt Lake And Utah Valleys Before The Mormon Immigration, John Homer Wakefield May 1933

A Study Of The Plant Ecology Of Salt Lake And Utah Valleys Before The Mormon Immigration, John Homer Wakefield

Theses and Dissertations

This study is an attempt to bring together such available material , heretofore not collected, into a single compilation pertaining to the plant associations of Utah and Salt Lake Valleys. An endeavor is made to build a picture of the vegetation as it was before the pioneers entered these valleys as compared with what it is today. The material compiled here is the result of searching through all available sources such as government reports of geological explorations, private diaries of explorers and pioneers , contemporary magazines, books and newspapers .


A Morphological And Systematical Study Of The Genus Brachinus Of The United States, Almon L.D. Brown May 1932

A Morphological And Systematical Study Of The Genus Brachinus Of The United States, Almon L.D. Brown

Theses and Dissertations

The genus Brachinus belongs to the well-known family Carabidae, commonly known as "Ground Beetles". About 15,000 species of Carabidae have been described, of which over 100 genera and 1,200 species occur in the United States. (Dodd Mead 1928).


The Rise And Development Of The Megagametophyte In Fritillaria Pudica And Fritillaria Atropurpurea, A Thesis Submitted To The Department Of Botany And The Graduate Council Of The Brigham Young University In Partial Fulfillment Of The Requirements For The Degree Of Master Of Science, Bertrand Fereday Harrison May 1931

The Rise And Development Of The Megagametophyte In Fritillaria Pudica And Fritillaria Atropurpurea, A Thesis Submitted To The Department Of Botany And The Graduate Council Of The Brigham Young University In Partial Fulfillment Of The Requirements For The Degree Of Master Of Science, Bertrand Fereday Harrison

Theses and Dissertations

The purpose of this thesis is to present the results of a morphological investigation of the megagametophytes of two species of Fritillaria. The author has attempted to present the data in sufficient detail to clearly picture the significant features in the histories of this gametophyte generation without unnecessary repetition. The data are presented as their chronological sequence dictates.


A Preliminary Study Of The Flora Of The Henry Mountains Of Utah, W. D. Stanton May 1931

A Preliminary Study Of The Flora Of The Henry Mountains Of Utah, W. D. Stanton

Theses and Dissertations

The Henry Mountains from the standpoint of plant geography are among the most interesting in the Rocky Mountain Region for they are entirely surrounded by desert and their unique location results in an intermingling of southern , eastern , and northern forms in the flora of this vicinity . In spite of these facts very little collecting or floral study has been done here and the Henry Mountains are still almost unknown floristically . This is unfortunate for much of the original vegetation has changed due to overgrazing by sheep . This preliminary study was undertaken with the view of …


The Distribution, Taxonomy And Ecology Of The Genus Salix Of Utah County, Utah, Kenneth Edward Weight May 1928

The Distribution, Taxonomy And Ecology Of The Genus Salix Of Utah County, Utah, Kenneth Edward Weight

Theses and Dissertations

The purpose or this paper is to make the willows of Utah end especially Utah County familiar to persons of moderate taxonomic skill. The Willow Family has become somewhat neglected by classes in taxonomy and the botanist in general because of not having a key -- except in one or two cases, that takes into consideration characters other than the fruits or capsules. To identify a willow in late summer is almost impossible by the beginning botanist, because few, if any, flowers, fruits and capsules can be found. In this paper external cheracters will be considered in descriptions. It must …


Distributional List Of The Birds In Utah, Clarence Cottam May 1927

Distributional List Of The Birds In Utah, Clarence Cottam

Theses and Dissertations

Systematic ornithology has been woefully neglected in Utah. While this state has a number of men who know her birds and who have aroused interest in them, they have produced no published record of what we have. So far as the writer knows there is no adequate, representative, or systematic collection of Utah species within the state. Utah has, however, been fortunate in having a nuraber of expert ornithologists collect and study the bird life of different sections of bar territory.


A Text And Manual Of Timpanogos Mosses, Seville Flowers Jan 1926

A Text And Manual Of Timpanogos Mosses, Seville Flowers

Theses and Dissertations

This present paper is an attempt to open the field of bryology in the state of Utah. It is necessarily a limited treatment both from the standpointof the number of species and the area. It represents the efforts of one summer's collection and the preparation of the manuscript and illustrations. The collection was taken at Mount Timpanogosby the students of the Alpine Summer School of the Brigham Young University during the 1925 session.


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.