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Full-Text Articles in Life Sciences
A Preliminary Investigation Of The Role Of Selenium In The Growth Of Stanleya Pinnata, Richard F. Nelson
A Preliminary Investigation Of The Role Of Selenium In The Growth Of Stanleya Pinnata, Richard F. Nelson
Theses and Dissertations
Stanleya pinnata has been identified as an indicator plant for seleniferous soils. The apparent limitation of its distribution to seleniferous soils suggests that selenium may play an essential role in this species. This study is a preliminary investigation of the role of selenium to Stanleya pinnata. When fully ripe, seeds germinated readily. Concentrations of selenium of 100 parts per million and 1000 parts per million retarded germination. Seeds germiuated in lower concentrations were not affected which was probably due to the selenium content of the seed itself, being greater than in the germinating media. Stanleya pinnata plants were grown from …
Studies On The Periodicity Of Certain Plankton Species Of Salem Lake, Gene A. Pratt
Studies On The Periodicity Of Certain Plankton Species Of Salem Lake, Gene A. Pratt
Theses and Dissertations
Plankton samples were taken periodically from one station in Salem Lake from the fall of 1955 through the winter of 1957. Other data including the pH, dissolved oxygen content, turbidity, brightness of day, temperature, and time of day were recorded at the time of each collection. The plankton samples were centrifuged and preserved in a 4% formalin solution. They were later examined microscopically, and density, percent density, and percent frequency calculations were made from them for ten selected species and for the five phyla which they represent.
Chemosynthetic Microorganisms In Leaching Sulfide Minerals, A. Keith Jameson
Chemosynthetic Microorganisms In Leaching Sulfide Minerals, A. Keith Jameson
Theses and Dissertations
This investigation showed that a single bacterium was capable of sulfide oxidation in exposed ore bodies. This single bacterium was isolated and characterized. It exhibited different characteristics than any previously known organism. It was found to be a chemosynthetic autotroph. An optimum nutrient concentration was determined for pyrite oxidation. The nutrient concentration was determined for pyrite oxidation. The nutrient contains only a source of phosphate and nitrogen. Urea was found to be a better source of nitrogen than ammonium sulfate which had previously been used. The effect of various organic compounds on the oxidation of pyrite was observed. Glucose and …
A Morphological Study Of Some North American Sitona (Coleoptera: Curculionidae), George J. Kidd
A Morphological Study Of Some North American Sitona (Coleoptera: Curculionidae), George J. Kidd
Theses and Dissertations
This study was undertaken to identify, if possible, some morphological characteristics of the U. S. Sitona species that would help simplify the classification of this difficult group. Because of extreme difficulty in obtaining positively identified specimens of all species reported, the scope was limited to eight identified species and one unidentified series. External structures studied include mouth parts, appendages, eyes, wings, and genitalia. The spermathecae were the only internal structures analyzed. Mandibular profiles were compared throughout the species represented and variations were noted. Labia and maxillae were observed but no distinctive differences were noticed. Antennae were found to be quite …
The Incidence Of Nasal Mites In Over-Wintering Red-Wing Blackbirds In The Vicinity Of Utah Lake, Utah, George M. Talley
The Incidence Of Nasal Mites In Over-Wintering Red-Wing Blackbirds In The Vicinity Of Utah Lake, Utah, George M. Talley
Theses and Dissertations
This paper reports the incidence and associations of four species of mites, Paraneonyssus icteridius, Ptilonyssus n. sp. "A", Sternostoma n. sp. "A" , and Speleognathus sp., found in the nasal cavities of the common red-wing blackbird (Agelaius phoeniceus ssp.) and Brewer's blackbird (Euphagus cyanocephalus cyanocephalus Wagler) over-wintering in the vicinity of Provo, Utah County, Utah. Three species of mites are reported for the first time from these birds, and two of these three are undescribed species.
The Embryology Of The Paradise Fish, Macropodus Opercularis Linnaeus, Lewis M. Mulkay
The Embryology Of The Paradise Fish, Macropodus Opercularis Linnaeus, Lewis M. Mulkay
Theses and Dissertations
The development of Sacropodus opercularis Linnaeus, (Perciformes: Anabantidae), is described from cleavage to five days post hatching. For the most part M. opercularis follows the pattern of typical teleostean development except as noted below: 1. The heart develops under the left eye along the anterior margin of the yolk sac. This is similar to that reported by Ingesoll (1951) for the Blue Gourami, Trichogaster trichopterus. 2. The ear develps from the head mesenchyme alongside the brain rather than from a placode. 3. The gut develops first in the posterior region then differentiates cephalad. It was also learned that: 1. No …
Oviposition Habits Of The Tick Dermacentor Parumapertus Neumann And Factors Influencing Egg Development, Clive D. Jorgensen
Oviposition Habits Of The Tick Dermacentor Parumapertus Neumann And Factors Influencing Egg Development, Clive D. Jorgensen
Theses and Dissertations
This paper includes data concerning the influence of relative humidity, temperature, and percentage of engorgement on the pre-oviposition period, oviposition period, post-oviposition period, and incubation period of the tick Dermacentor parumapertus Neumann. The influence of the percentage of engorgement on the oviposition period, oviposition rate, and egg number is considered. Data on the disposition and number of eggs in nature are discussed.
A Taxonomic Study Of The Families Of Utah Coleoptera Excluding Rhynchophora, T. Blaine Moore
A Taxonomic Study Of The Families Of Utah Coleoptera Excluding Rhynchophora, T. Blaine Moore
Theses and Dissertations
During the years 1950-51 work was begun on a study of the Coleoptera by the author. In 1955, due to the lack of a workable set of keys to the Coleoptera of Utah, a study was undertaken to find a way to more easily classify the beetles of the state to their respective families. The collection of Brigham Young University was used as the basis for determining the families of beetles actually found in Utah. Then a thorough search of the literature was made to find positive records of Utah families not represented in that collection. It was found that …
An Ecological Survey Of The Vegetation Of The Dinosaur National Monument, Utah, Stanley L. Welsh
An Ecological Survey Of The Vegetation Of The Dinosaur National Monument, Utah, Stanley L. Welsh
Theses and Dissertations
The present work is a general survey of the vegetation of the Utah portion of the Dinosaur National Monument with special emphasis on some of the ecological aspects of the area. The vegetation ranges from xerophytic plant communities of the lower elevations to mesophytic communities of the higher elevations. Hydrophytic plant communities are also present to a limited extent along the Green River and where seeps or springs arise. Soils vary from fine clay to coarse gravel. The dividing lines between formations is often marked by extreme differences in soil type. During the author's first collecting trip into the Monument …
Introgression In Purshia Tridentata (Pursh) Dc. And Cowania Stansburiana Torr, Lindsey Kay Thomas
Introgression In Purshia Tridentata (Pursh) Dc. And Cowania Stansburiana Torr, Lindsey Kay Thomas
Theses and Dissertations
A study ot discordant variation in populations of Purshia tridentata, Purshia glandulosa, and Cowania Stansburiana has disclosed that introgressive hybridization can be expected whenever these species come in contact with each other. The introgression is not only of one pure species into that of another, but is also of introgressed populations into other introgressed populations and of pure populations into introgressed populations. Evidence was found showing that in all probability Purshia glandulosa is a stabilized segregant derived from introgressed populations. Evidence was also found and presented to show that introgression is responsible for the recent acquisition of stalked hypanthium glands …