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Full-Text Articles in Life Sciences

The Female Genitalia And Spermathecae Of Some Of The Rhynchophora, Herman O. Sanders Mar 1951

The Female Genitalia And Spermathecae Of Some Of The Rhynchophora, Herman O. Sanders

Theses and Dissertations

In this study of the genitalia and spermathecae of the Rhynohophora, eighty-two species, representing sixty genera, were examined as listed in Leng's Catalogue of Coleoptera of North America North of Mexico, together with seven species from the Phillippine Islands and one from China. By using the external female genitalia and spermathecae the Rhynochophora studied may be divided into eight and possibly nine well-defined groups. They are separated into these groups on the basis of the development of the nodulus and ramus and upon the degree of crenulation that occurs in the spermatheca. The spermatheca of all species studied has been …


A Comparative Study Of The Osteology And Myology Of The Thoracic Limb Of The Pocket Gopher And Kangaroo Rat, Leland R. Allen Dec 1950

A Comparative Study Of The Osteology And Myology Of The Thoracic Limb Of The Pocket Gopher And Kangaroo Rat, Leland R. Allen

Theses and Dissertations

The purpose of this study was to determine the morphological differences in the osteology and musculature of the thoracic limb of the pocket gopher and kangaroo rat. This was accomplished by first, collection of specimens, second, the preservation and preparation of bones and muscles tor study and illustration, third, sketching and photograph­ing the sketches, fourth, noting and recording origins and insertions as well as any differences in the modification of anatomy with relation to habitat requirements. These two closely related families, Geomyide and Heteromyidae, show great morphological differences. Comparative volumetric measurements show that the forelimb of the pocket gopher is …


Some Observations On The Embryology And The Weberian Apparatus Of Catostomus Ardens (Jordan And Gilbert), H. Ronald Frogley May 1950

Some Observations On The Embryology And The Weberian Apparatus Of Catostomus Ardens (Jordan And Gilbert), H. Ronald Frogley

Theses and Dissertations

The purpose of this study is to add to our knowledge of the embryology and osteology of the Weberian apparatus as found in the sucker, Catostamus ardens J. & G. ot Utah Lake. Observations were made on the embryological development for twenty one days. This information has been discussed and pictures showing the development included. The literature on the osteology ot the Weberian apparatus was reviewed and it is believed that this study presents the first descriptions of the bones of this species. The ossicles were found to be comparatively stable within species indicating some taxonomic value. More study is …


A Comparative Histological Study Of The Adrenal Gland Of Native Rabbits, Ernest I. Gonzalez May 1950

A Comparative Histological Study Of The Adrenal Gland Of Native Rabbits, Ernest I. Gonzalez

Theses and Dissertations

A review of the literature shows that extensive work has been done on the morphology and histology of the adrenal gland of the domesticated rabbit, but it appears that little or no work has been done on other members of the order Lagomorpha. Approximately one hundred specimens of rabbits of various ages and sizes, and of both sexes, were collected over a period of nine months. All adrenal glands were fixed by immersion and were embedded in paraffin. The majority or the glands were sectioned at eight or twelve miora, and were stained with Mallory's triple stain. This investigation shows …


A Comparative Anatomical Study Of The Digestive Systems Of The Desert Jack Rabbit And The Pika, Dale Stanley Rupert Feb 1950

A Comparative Anatomical Study Of The Digestive Systems Of The Desert Jack Rabbit And The Pika, Dale Stanley Rupert

Theses and Dissertations

It is the purpose of this study to make gross and histological comparisons of the various segments of the intestinal tracts of the jack rabbit and the pika. The two animals used for this study were the desert jack rabbit (Lepus Californicus deserticola Mearns), and the pika (Ochotona princepts uinta Hollister). The jack rabbits were found only in the desert valleys and low foothills in the areas studied. These areas are typically open bush or sage brush types of communities. The pikas were restricted to certain high rockslides in this region. These areas are described more completely in the section …


A Preliminary Study Of The Siphonapterous Ectoparasites Found On The Mammals Of The Families Cricetidae And Muridae In Utah County, Vernon J. Tipton May 1949

A Preliminary Study Of The Siphonapterous Ectoparasites Found On The Mammals Of The Families Cricetidae And Muridae In Utah County, Vernon J. Tipton

Theses and Dissertations

The purpose of this study was to determine the species of fleas infesting the mammals of the families Cricetidae and Muridae in Utah County. This was accomplished by establishing twelve collecting stations throughout the county from which 198 mammals were collected. From these hosts, 392 fleas were collected representing three families, nineteen genera , and twenty-four species. Four species are new to the State of Utah and twenty-two species are recorded from Utah County for the first time.


Life History Studies Of The Mouse, Peromyscus Truei Nevadensis, Lowell S. Miller Jun 1947

Life History Studies Of The Mouse, Peromyscus Truei Nevadensis, Lowell S. Miller

Theses and Dissertations

Peromyscus truel's a fairly common inhabitant of the upper sonaranlife zone of the Western States. It is an excellent laboratory anlmal with the limitation that captivity must be accompanied by forced activlty, in order to keep the animals within the limits of normal activity. This mouse is polyestrous and breeds from early spring to late fall. Observations have shown pregnancy in late September and in early February. It is the writer's belief that ovulation in the ovary occurs only when copulation has taken lace, because corpora lutea has only been found in pregnant or lactating females. The evidence is scanty …


A Seasonal Study Of Food Of Some Birds Of The Wasatch Chaparral, Herbert H. Frost May 1947

A Seasonal Study Of Food Of Some Birds Of The Wasatch Chaparral, Herbert H. Frost

Theses and Dissertations

A seasonal change occurred in the type of food consumed by the birds studied. Plant food was more important in the winter than in the summer. Animal food, except in one species, was found to be more important during the summer months. The most important plant foods determined by frequency and listed in order of their abundance were: Helianthus annuus, Celtis sp., Quercus sp., Polygonum convolvulus, Amaranthus blitoides, Chenopodium album, and Amaranthus graecizans. The most important animal foods based on occurance in stomachs examined were: Coleoptera, Hymenoptera, Lepidoptera larvae, Orthoptera, Undetermined larvae, Diptera, Homoptera, Coleoptera larvae, Araneae, and Hemiptera. Seventeen …


A Taxonomic Study Of The Adult Mosquitoes Of Utah County With Notes On The Biology And Distribution Of The More Common Species 1946-1947, Cluff E. Hopla May 1947

A Taxonomic Study Of The Adult Mosquitoes Of Utah County With Notes On The Biology And Distribution Of The More Common Species 1946-1947, Cluff E. Hopla

Theses and Dissertations

In Utah County, information has been lacking concerning the taxonomy and distribution of mosquitoes. With the knowledge of this condition, it is felt that information can be presented which will be of value both to the scienoe of Entomology and the area concerned.


History Of The Cotton Mission And Cotton Culture In Utah, Ivan J. Barrett Jan 1947

History Of The Cotton Mission And Cotton Culture In Utah, Ivan J. Barrett

Theses and Dissertations

The writer, being interested in the agricultural project of cotton growing in early Dixie, and finding scarcely anything written on the subject, has gone into the original sources, histories, journals, diaries, etc., and found a reservoir of enlightenment regarding cotton culture in Utah's Dixie. He has tried to assemble from the most important sources, an informative yet interesting study of cotton culture in Utah. The writer in no wise pretends to have exhausted the subject, nor to have reached all the sources. Many of those early cotton growers who did most to produce this staple, kept no record of their …


The External Male Genitalia Of Some Rhynchophora, Arthur F. Bruhn May 1946

The External Male Genitalia Of Some Rhynchophora, Arthur F. Bruhn

Theses and Dissertations

Today there is an increasing recognition among taxonomists of the importance of consideration of the complete morphology of insects in classifying them and in arrangming them in their logical phylogenetic sequence. Regarding the Rhynohophora, with which this paper is concerned, some progress toward a more complete understanding has been made. In 1912 Sharp and Muir made a study of the male genital tube of the coleoptera in general and observed that the various specializations they noted in the forms of Rhynohophora examined would doubtless be of future significance. Tanner in 1927 made a similar important study of the female genitalia …


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.