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Theses and Dissertations

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Full-Text Articles in Life Sciences

A Study Of Growth Rates In Seedlings Of Douglas Fir Ecotypes, Herbert D. Papenfuss May 1964

A Study Of Growth Rates In Seedlings Of Douglas Fir Ecotypes, Herbert D. Papenfuss

Theses and Dissertations

The purpose of this study was to find out if ecological races with different growth rates existed in douglas fir. Seeds were collected from six areas by the Forest Service and the author. A study was made of stem and tap root growth utilizing three photoperiods of varying length. Rate of tap root growth was significant for ecotype suggesting selection for tap root length in the plants from utah and Arizona. Each geographical area represents a growth rate ecotype with a wide break in the data on stem growth.

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A Comparative Osteological Study Of Two Species Of Colubridae (Pituophis And Thamnophis), Robert E. Bullock May 1964

A Comparative Osteological Study Of Two Species Of Colubridae (Pituophis And Thamnophis), Robert E. Bullock

Theses and Dissertations

With reference to anatomical studies it appears that the aerpents are indeed a neglected group ot reptiles. Although some early writers recorded a few fragmentary obser-vations on the anatomy of snakes, no attempt was made to undertake a complete comprehensive study. Cole (1944) has rightfully referred to this section of vertebrate anatomy as "almost virgin field." The serpent area of reptilian anatomy is deserving ot a more intensive investigation because of the considerable number ot adaptations demonatrated by this group of reptiles in relation to their peculiar types ot locomotion and methods ot feeding. It is important to understand the …

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A Taxonomic Study Of Fleas Of The Genus Foxella (Wagner) In Utah (Siphonaptera: Dolichopsyllidae), Robert A. Amoureux Apr 1964

A Taxonomic Study Of Fleas Of The Genus Foxella (Wagner) In Utah (Siphonaptera: Dolichopsyllidae), Robert A. Amoureux

Theses and Dissertations

Fleas of the genus Foxella Wagner, commonly known as "gopher fleas," have various species of the mammal genus Thomomys Weid Neuweid in the Western United States as their hosts. Some workers maintain there are at least two species of fleas while others consider that all gopher fleas are of one species.

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Changes In The Vegetation Of Two Restricted Areas Of The Wasatch Plateau As Related To Reduced Grazing And Complete Protection, Hyrum B. Johnson Jan 1964

Changes In The Vegetation Of Two Restricted Areas Of The Wasatch Plateau As Related To Reduced Grazing And Complete Protection, Hyrum B. Johnson

Theses and Dissertations

An understanding of the interactions betnen vegetation and livestock grazing is of paramount importance to the welfare of the livestock industry. It is also important to know how these interactions affect the balance of the ecosystem. In general, observations of changes in vegetation provide an index for evaluating such interactions. Vegetation change is the main object of consideration in this paper. The study is concerned with some of the oldest pemanent native vegetation study plots in the Western United States. They are located on Horseshoe Flats of the Wasatch Plateau in Central Utah.

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Ecology Of Summer Aquatic Invertebrate Populations In A Marsh Area Of Utah Lake, David A. White Aug 1963

Ecology Of Summer Aquatic Invertebrate Populations In A Marsh Area Of Utah Lake, David A. White

Theses and Dissertations

Mud Lake marsh lies east of Utah Lake between the cities of Provo and Springville in Utah County. Since 1936 it has become a polluted, odiferous, silted area. A study was conducted on the aquatic invertebrates during the summer of 1962 (June 19 to September 20). An .01 meter2 bottom sampler was used at 30 random stations. Each station was sampled once a week. Water depth, mud, water and air temperatures were taken at each station. Dissolved oxygen (Winkler method) and ion resistance (Wheatstone bridge) were taken each day. The aquatic invertebrate community consisted of benthic (Diptera, Oligochaeta, Nematoda), interphashic …

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The Darkling Beetles Of The Nevada Test Site (Coleoptera - Tenebrionidae), Willis A. Packham Jul 1963

The Darkling Beetles Of The Nevada Test Site (Coleoptera - Tenebrionidae), Willis A. Packham

Theses and Dissertations

In the desert areas of southwestern United States the Coleoptera, family Tenebrionidae, constitute a conspicuous part of the ground-dwelling insects. Most species are black or dull chestnut-brown. They are primarily nocturnal and during the day can be found under rocks, debris, loose bark, or in rodent burrows. On cloudy days they may be seen lumbering along the desert floor. Most tenebrionids feed on plant materials of various sorts. In August, 1959, Brigham Young University initiated an ecological study at the Nevada Test Site near Mercury in Nye County, Nevada. As part of that study, emphasis was given to the ground-dwelling …

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A Comparative Study Of The Osteology And Myology Of The Hind Limb Of The Pocket Gopher And Kangaroo Rat, Nancy S. Price Jul 1963

A Comparative Study Of The Osteology And Myology Of The Hind Limb Of The Pocket Gopher And Kangaroo Rat, Nancy S. Price

Theses and Dissertations

The purpose of this study was to compare the morphology of the hind limb of the pocket gopher with that of the kangaroo rat and to determine their differences. This was accomplished by first, obtaining the specimens; second, preparation of the specimens for preservation and dissection; third, photographing and tracing the muscles; fourth, noting the origin and insertion of each muscle and their general morphology; and fifth, preparation and photographing of the bones. Comparative volumetric measurements were made of the muscles of the two animals to determine the differences between them. These two families, Geomyidae and Heteromyidae, are closely related …

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A Study Of The Morphology And Systematics Of The Genera Polydrusus And Scythropus (Coleoptera: Curculionidae), Gary L. Jensen Jul 1963

A Study Of The Morphology And Systematics Of The Genera Polydrusus And Scythropus (Coleoptera: Curculionidae), Gary L. Jensen

Theses and Dissertations

The objectives of this study were 1) to further clarify the status of the genera Polydrusus and Scythropus and 2) to redescribe and elucidate the morphology and distribution of the species of Scythropus in order to better facilitate their identification. Some 1650 specimens were used in the study and about 300 of these were critically examined for morphological variations of the head, beak, antennae, thorax, elytra, abdomen, integument, legs, genitalia, and eighth tergite and ninth segment of the male. Over one hundred genitalia were dissected and critically examined for good characters. The male genitalia were the most reliable single characters …

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Seasonal Study Of Mites On Deer Mice (Peromyscus Maniculatus) In A Chaparral Community, Donald B. Ash Jul 1963

Seasonal Study Of Mites On Deer Mice (Peromyscus Maniculatus) In A Chaparral Community, Donald B. Ash

Theses and Dissertations

The parasitic mites on mammals living in the chaparral community of Utah are practically unknown ecologically. Keegan (1953) was the first to publish on parasitic mites from Utah. He listed mites of 12 species and 9 genera from Tooele and Juab counties from hosts which included one Peromyscus truei, five P. crinitus, and 20 P. maniculatus. Brennan and Beck (1955) published on the chiggers of Utah and included a key to 38 species. Allred (1954, 1956, 1957, 1958) studied the geographical distribution, seasonal occurrence, and biology of mites found on mice of the genus Peromyscus in Utah.

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Cytological Evidence For Reciprocal Introgression In Agropyron Trachycaulum And Agropyron Spicatum, Laval M. Pitts Jul 1963

Cytological Evidence For Reciprocal Introgression In Agropyron Trachycaulum And Agropyron Spicatum, Laval M. Pitts

Theses and Dissertations

Agropyron trachycaulum (Link) Malte and Agropyron spicatum Pursh, both native range grasses of the Great Basin, often hybridize in nature. A. trachycaulum, is a tetraploid with 28 chromosomes. It has awnless or awntipped lemmas and small anthers. A. spicatum is a diplois with 14 chromosomes. It is characterized by having long awn that bend at maturity, and anthers which are about four times longer than A. trachycaulum. Artificial hybrids are intermediate between parents in awn and anther lengths and have 21 chromosomes. A natural population in Utah was found consisting of A. trachycaulum, A. spicatum, plants resembling the artificial hybrids, …

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Parasitic Mites Of Kangaroo Rats Of The Nevada Atomic Test Site, Morris A. Goates Jun 1963

Parasitic Mites Of Kangaroo Rats Of The Nevada Atomic Test Site, Morris A. Goates

Theses and Dissertations

A systematic study of parasitic mites on kangaroo rats at the Nevada Test Site, Nye County, Nevada, was conducted from August, 1959, to December, 1961. The intent was to determine their kinds, numbers, seasonal occurrence, and ecological relationship with Dipodomys merriami merriami Mearns and Dipodomys microps occidentalis Hall and Dale in nuclear disturbed and contiguous undisturbed areas. Study areas were established in three major valleys -- Jackass Flats, Yucca Flat, and F renchman Flat.

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A Study Of The Coprophilous Ascomycetes Of Utah, David L. Hanks May 1963

A Study Of The Coprophilous Ascomycetes Of Utah, David L. Hanks

Theses and Dissertations

Specimens of animal dung were collected from various areas of the state of Utah. These were cultured by placing a few small pieces in a culture dish over moistened sphagnum moss and filter paper. The cultures were observed periodically and specimens were studied as they matured upon the substratum. A total of eighty-four species representing three orders and fifteen genera are reported. Of these, nine species have not previously been described. Included is one species, Tripterospora erostrata, from the order Plectascales of the Series Plectomyceteae. Cited from the order Sphaeriales of the Series Pyrenomyceteae are forty-nine species as follow: Coniochaeta, …

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Vegetational Changes Of The Uinta Basin Since Settlement, Bernard Curtis Dastrup Jan 1963

Vegetational Changes Of The Uinta Basin Since Settlement, Bernard Curtis Dastrup

Theses and Dissertations

A general survey of the vegetational changes of the rangelands of the Uinta Basin was made using historical records, documents, interviews, and recent vegetational surveys. Historical vegetatienal information about the Uinta Basin is very limited, most of it pertaining to the vegetation along the streams and rivers. Escalante, in 1776, mentioned the splendid groves of cottonwoods, the fine pastures, and the abundance of game along the rivers. Ashley in 1825 and Powell in 1870 entered the Basin via the Green River. Ashley crossed the Basin following the Duchesne River and its tributary the Strawberry River. He described the groves of …

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Differential Salt Tolerance Of Hordeum Jubatum, Agropyron Trachycaulum, And Their Natural Hybrid Elymus Macounii, Marian Lucy Hanna Aug 1962

Differential Salt Tolerance Of Hordeum Jubatum, Agropyron Trachycaulum, And Their Natural Hybrid Elymus Macounii, Marian Lucy Hanna

Theses and Dissertations

Because plants show a wide range of variation in growth in the presence of excessive concentrations of soluble salts in the soil, this study was undertaken to determine the effects of various concentrations of NaCL and Na2SO4 on the growth and development of Hordeum jubatum, Agropyron trachycaulum, and the natural hybrid of these two plants, Elymus macounii.

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The Taxonomic Problem Of Polycelis In The United States, Lee F. Braithwaite Jul 1962

The Taxonomic Problem Of Polycelis In The United States, Lee F. Braithwaite

Theses and Dissertations

During the spring of 1941, Dr. C.L. Hayward, of the Brigham Young University zoology department, while on a field trip with his ecology class found some interesting planaria.ns at a place called Stewart's Flats on Mt. Timpanogos, Utah County, Utah. A fellow teacher, Dr. D. E. Beck, sent live specimens to Dr. L. H. Hyman of the American Museum of Natural History for identification. Although the specimens arrived in New York as a "putrid smelling soup,"1 the specimens, through correspondence, were thought to be Polycelis coronata (Girard), the same species Hyman collected in South Dakota during August 1929.

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Vertebrate Distribution In Relation To Certain Habitats In Central Kane County, Utah, Clyde L. Pritchett Jun 1962

Vertebrate Distribution In Relation To Certain Habitats In Central Kane County, Utah, Clyde L. Pritchett

Theses and Dissertations

This thesis is a study of vertebrate distribution in relation to certain habitats in cetral Kane County, Utah. Four areas were trapped, two in a sagebrush community and two in a grassland community. Oryzopsis hymenoides (Roem & Shult.) Ricker, Hilaria jamesii (Torr) Benth., Ephedra torreyana S. Watts and Guttierrezia sarothrae (Purah.) Britt and Rusby, were the dominant plants in the grassland community. The dominant plants in the sagebrush community were Artemisia tridentata Nutt., and Hilaria jamesii (Torr.) Benth. Dipodomys ordii cupidineus Goldman was the most common mammal trapped in both communities. Peromyscus maniculatus sonoriensis (LeConte) was trapped most often in …

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Perennial Atriplex Of Utah And The Northern Deserts, Craig A. Hanson Jan 1962

Perennial Atriplex Of Utah And The Northern Deserts, Craig A. Hanson

Theses and Dissertations

Atriplex is a genus in the Chenopodiaceae, the perennial members of which are ecologically important in western North America. Seventeen species and one subspecies of perennial Atriplex occur in Utah and the northern deserts. Three of these species and the subspecies were described by the writer in a recent publication as a result of extensive field work leading to this study. These are A. welshii, A. navajoensis, A. bonnevillensis, and A. cuneata ssp. introgressa. This study is an investigation of the systematics and phytogeography of the perennial Atriplex in Utah and the northern deserts, with emphasis on the A. gardneri …

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An Analysis Of A Hybrid Complex Involving Agropyron Subsecundum, Agropyron Trachycaulum And Elymus Glaucus, Lewis Kay Shumway Aug 1961

An Analysis Of A Hybrid Complex Involving Agropyron Subsecundum, Agropyron Trachycaulum And Elymus Glaucus, Lewis Kay Shumway

Theses and Dissertations

In the past twenty years many workers have made contributions to a better understanding of hybridization and introgression through studies of members of the grass family. The present study is an attempt to increase the understanding of the importance and amount of hybridization and introgression in members of the Tribe Hordeae. This study is concerned with a hybrid complex involving Agropyron subsecundum (Link) Hitchc. (bearded wheatgrass), Agropyron trachycaulum (Link) Malte (slender wheatgrass) and Elymus glaucus Buckl. (blue wild rye).

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An Ecological Study Of An Exclosure In The Mountain Brush Vegetation Of The Wasatch Mountains, Utah, Elray S. Nixon Aug 1961

An Ecological Study Of An Exclosure In The Mountain Brush Vegetation Of The Wasatch Mountains, Utah, Elray S. Nixon

Theses and Dissertations

This is a comparative study of the vegetation and soils of an exclosure in the mountain brush vegetation of the Wasatch Mountains, Utah. The exclosure was fenced and initially analyzed during the summers of 1949-1950. The study area is located in Pole Canyon in the Uinta National Forest, a few miles northeast of Provo, Utah. The dominant woody species of the vegetation in the exclosure are big toothed maple (Acer grandidentatum) and Gambel oak (Quercus gambelii). After settlement of the area in and around Provo, Pole Canyon became overgrazed by livestock. Since 1949 the area has been protected from grazing. …

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A Morphological Study Of Some Larval Ticks Of The Genus Dermacentor With Emphasis On Structures Of Possible Taxonomic Importance, Richard Grant Robertson Jul 1961

A Morphological Study Of Some Larval Ticks Of The Genus Dermacentor With Emphasis On Structures Of Possible Taxonomic Importance, Richard Grant Robertson

Theses and Dissertations

This study was undertaken to evaluate and determine morphological characteristics which might prove valuable in the identification of the larvae of the following species of ticks of the genus Dermacentor Koch: D. albipictus Packard, D. andersoni Stiles, D. hunteri Bishop, D. parumapertus Neuman, and D. variabilis Say. A taxonomic key for the identification of all of the Canadian and United States species of the larvae of the genus Dermacentor Koch cannot be constructed until specimens of D. halli and D. occidentalis have been examined. However, the followng conclusions were reached regarding the species studied: 1. Position of setae is of …

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Bark Beetles Of The Genus Dryocoetes (Coleoptera: Scolytidae) In North America, Donald Edward Bright Jr. Jun 1961

Bark Beetles Of The Genus Dryocoetes (Coleoptera: Scolytidae) In North America, Donald Edward Bright Jr.

Theses and Dissertations

The genus Dryocoetes is widely distributed in Europe, Asia, North America and Central America. It consists of about sixty species, seven of which occur in North America.

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Classification And Distribution Of The Native Trees Of Utah, Kimball Steward Erdmann Jun 1961

Classification And Distribution Of The Native Trees Of Utah, Kimball Steward Erdmann

Theses and Dissertations

This study is an attempt to consolidate the information already known about the trees of Utah and to extend our knowledge of these trees. An intensive study was made of the available literature. The tree specimens of the herbaria of the Utah State University, University of Utah, Brigham Young University and the Regional Office of the Forest Service at Ogden were examined. These studies were supplemented with extensive field work in various parts of the state. From this information, keys and descriptions of the genera and species were written and distribution maps for each tree and illustrations of many of …

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A Comparative Study Of The Axillary Sclerites In Coleoptera, Howard P. Shurtleff May 1961

A Comparative Study Of The Axillary Sclerites In Coleoptera, Howard P. Shurtleff

Theses and Dissertations

The axillary sclerites of 69 species representing 52 families of the order Coleoptera were examined and illustrations prepared of most or them. A description is given for the typical axillary sclerites and the deviations in form from this pattern are discussed for the major groups of beetles. The phylogenetic relationships between some families, and other groups, are pointed out based on the morphology of the axillary sclerites. Phyletic groups in Adephaga are characterized by the axillary sclerites, but in the Polyphaga variations are too numerous and inconsistant to be useful in determining phyletic trends.

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A Study Of The Effects Of Different Substrates On Growth And Reproduction In Certain Coprophilic Agaricaceae, Raymond C. Brown Dec 1960

A Study Of The Effects Of Different Substrates On Growth And Reproduction In Certain Coprophilic Agaricaceae, Raymond C. Brown

Theses and Dissertations

Psilocybe mutans sp. nov. had ceased fruiting consistently in artificial culture several years prior to the initiation of this study. In the couse of this study fruiting bodies were produced on a number of different substrates. All cultures were inoculated by mycelial transfer or by spraying with a suspension of pre-germinated spores. All cultrues were incubated for one to two weeks in a constant-temperature room at 70°F. on a shelf fourteen inches below a fluorescent lighting fixture. Lighting was continuous with an intensity at shelf level of approximately 3,000 foot-candles. Fruiting on any particular substrate was improved if the substrate …

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Observations On The Hibernation Of Culex Tarsalis Coquillett In Utah Valley, Utah, Dennis W. Trent Sep 1960

Observations On The Hibernation Of Culex Tarsalis Coquillett In Utah Valley, Utah, Dennis W. Trent

Theses and Dissertations

Culex tarsalis Coquillett is a common evening pest mosquito throughout the summer in most of temperate Western North America. Present evidence indicates this mosquito as the principal naturally infected vector of western equine encephalomyeltic (WEE) viruses. Certain interrelationships of WEE epidemiology and tarsalis bionomics are basically understood; however, in areas where winters are severe little is know of tarsalis hibernation, and the survival mechanism for WEE viruses in unknown. The purpose of this study, conducted from 1 September 1959 to 20 May 1960, was to gather ecological information on the hibernation of Culex tarsalis in Utah Valley, and secondly to …

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A Comparison Of The Root Systems Of Bitterbrush And Cliffrose, Morris G. Cline Sep 1960

A Comparison Of The Root Systems Of Bitterbrush And Cliffrose, Morris G. Cline

Theses and Dissertations

A root study was undertaken to learn about bitterbrush (Purshia tridentata (Pursh) DC) and cliffrose (Cowania stansburiana torr.) to gain some clues, perhaps, as to the causes of their present distribution. In a period extending from July 1959 to July 1960, twenty-four plants were excavated on six different sites in the Wasatch foothill belt in Utah County, Utah. Root and some soil characteristics were analyzed, described and compared.

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A Comparative Study Of Crotaphytus Holbrook (Iguanidae), Wilbur Gerald Robinson Aug 1960

A Comparative Study Of Crotaphytus Holbrook (Iguanidae), Wilbur Gerald Robinson

Theses and Dissertations

The anterior myology of Crotaphytus wislizeni and C. collaris is described in detail and a statistical analysis is made of the differences in the relative bone sizes, and the number of eggs per clutch, as well as other taxonomic characters previously applied to these species. The significant differences found with respect to the shape of the skull, that of the body, and the character of the hyoid are correlated with muscular development and habits of the two species. The descriptive material is accompanied by detailed myological and osteological illustrations of C. wislizeni. Comparative notes are made on C. reticulatus which …

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Lichens Of The Wasatch Mountains In Central Utah, Harry Stewart Nielsen Jr. Aug 1960

Lichens Of The Wasatch Mountains In Central Utah, Harry Stewart Nielsen Jr.

Theses and Dissertations

The purpose of this study is to conduct an intensive investigation of the lichen flora of the Wasatch Mountains in central Utah. The approach followed is that of compiling into one account keys, descriptions, illustrations and ecological notes of lichens that are found in this region of the state.

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The Vitamin B1-Sparing Action Of Sorbitol, Gisela Eleanor Bethsold Jun 1960

The Vitamin B1-Sparing Action Of Sorbitol, Gisela Eleanor Bethsold

Theses and Dissertations

The present study was initiated to determine the effect sorbitol has upon the enzymatic functions of thiamin; specifically, what effect sorbitol bas upon the alpha-ketoglutarate and pyruvate dehydrogenases activities of rat liver mitochondria. In addition, the effect of varying the dietary sorbitol concentration on the development of an athiaminosis was studied, particularly the effect on growth rate.

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The Aquatic Plants Of Central Utah And Their Distribution, Gerald E. Bessey May 1960

The Aquatic Plants Of Central Utah And Their Distribution, Gerald E. Bessey

Theses and Dissertations

It was the purpose of this study to determine what aquatic plants were common to central Utah and to outline the ecological factors that control their distribution. The main emphasis throughout has been upon the more macroscopic aquatic plants. Such algae were included as was warranted by their size,, abundance and importance in the various habitats in which they grew. As this study progressed it became evident that there was a need for a broad survey-type study of the aquatic plants that would include essentially all of the wet lands of the central Utah region. The area of study closely …

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