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Venezuelan Nycteribiid Batflies (Diptera: Nycteribiidae), Lindolpho R. Guimarães Sep 1972

Venezuelan Nycteribiid Batflies (Diptera: Nycteribiidae), Lindolpho R. Guimarães

Brigham Young University Science Bulletin, Biological Series

Eleven species of Nycteribiidae, all belonging to the genus Basilia, are reported from Venezuela. Of these, two (tuttlei and typhlops) are described as new and four (anomala, dubia, juquiensis, and tiptoni) are recorded for the first time. B. anomala is the first species with three tergal plates to be found in South America. Synonymies, previous localities, and host records are given for all species, as well as new records and comments. Geographical distribution and host-parasite associations are discussed. Field parties of the Smithsonian Venezuelan Project obtained the material on which this paper is based.

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Front Matter, Vol. 17 No. 5 Sep 1972

Front Matter, Vol. 17 No. 5

Brigham Young University Science Bulletin, Biological Series

No abstract provided.

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Front Matter, Vol. 16 No. 4 Sep 1972

Front Matter, Vol. 16 No. 4

Brigham Young University Science Bulletin, Biological Series

No abstract provided.

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The Effects Of Different Gases On Excystation Of Coccidian Oocysts, James B. Jensen Aug 1972

The Effects Of Different Gases On Excystation Of Coccidian Oocysts, James B. Jensen

Theses and Dissertations

Excystation of coccidian oocysts is a diphasic process where CO2 and suitable reducing agents cause changes in oocyst wall permeability (phase I) allowing the entrance of trypsin and bile which activate the sporozoites (phase II). This project was an indirect study of the mechanism of CO2 action by the substitution of NO, NO2, N2O, H2S, SO2 , CH4, NH3 and 8M urea in place of CO2. Changes in oocyst wall permeability of Eimeria stiedae, E. bovis and E. tenella were determined by incubation with the reagents and cysteine HCl followed by treatment with trypsin and bile to initiate activation of …

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Bionomics And The Influence Of Diet Upon The Maturation Of Orchopeas Leucopus (Baker), Lynden Phillip Baum Aug 1972

Bionomics And The Influence Of Diet Upon The Maturation Of Orchopeas Leucopus (Baker), Lynden Phillip Baum

Theses and Dissertations

Knowledge of the bionomics of plague vectors, es-pecially factors which influence life history, host pre-ference, and fluctuations of flea populations, are basic to an understanding of plague ecology. Orchopeas leucopus (Baker), an ectoparasite of cricetid rodents such as Peromyscus maniculatus (Wagner), and Peromyscus truei (Baird), is a vector of plague in the western United States (Holdenried and Morlan, 1955). In a study of nine biotic corrnnunities in the Utah portion of the Great Basin, P. maniculatus was the most abundant rodent in seven of the biotic corrnnunities (Olsen, 1966). Because of the ubiquitous nature of P. maniculatus an interchange of …

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A Genetic Study Of Gigas Atriplex Canescens, James Michael Melby Aug 1972

A Genetic Study Of Gigas Atriplex Canescens, James Michael Melby

Theses and Dissertations

A population of Atriplex canescens (Pursh) Nutt. (fourwing saltbush), endemic to the Little Sahara Sand Dunes near Jericho, Utah, appears to be genetically distinct from all other forms of this species. It differs from other populations by many characters, including growth rate, seed size, and height (Figures 1, 2, 3 and 4). This is a report of a study which was made to investigate the differences between the sand dune and normal populations, and an attempt to determine the evolutionary processes involved in the formation of the sand dune population.

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Population Dynamics Of Fleas (Siphonaptera) On The Uinta Ground Squirrel, Spermophilus Armatus Kennicott, Dennis I. Anderson Aug 1972

Population Dynamics Of Fleas (Siphonaptera) On The Uinta Ground Squirrel, Spermophilus Armatus Kennicott, Dennis I. Anderson

Theses and Dissertations

The Uninta ground squirrel, Spermophilus armatus Kennicott, is the most abundant diurnal rodent in the Wasatch Mountains at the 7,000-9,000 foot level particularly in the campgrounds and picnic areas. Contact between man and the Uninta ground squirrel may be hazardous inasmuch as the causative agent of plague has been isolated from S. armatus and its flea parasites (Public Health Reports, 1937, 1938a, 1938b; Meyer, 1938; Byington, 1940; Allred, 1951; and Beck, 1955). Since these fleas are vectors of sylvatic plague and potential vectors of human plague, detailed knowledge about their population dynamics is desirable.

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Embryology And Larval Development Of Acteon Punctocoelata (Carpenter) (Gastropoda, Opisthobranchiata), Scott E. Brown Aug 1972

Embryology And Larval Development Of Acteon Punctocoelata (Carpenter) (Gastropoda, Opisthobranchiata), Scott E. Brown

Theses and Dissertations

Acteon (Rictaxis) punctocoelata (Carpenter) is a primitive opisthobranch mollusc found sporadically in central California bays. The primitive nature of this genus is indicated both geologically and morphologically (Fretter and Graham, 1954 and Morton, 1958). This micro-phagous browser burrows just below the surface of the sandy mudflats, as do its close relatives Harninea, Scaphander, and Philine (Fretter and Graham, 1954). Its strong, sculptured external shell is approximately 1/2 inch long and is encircled with narrow black· bands that follow the whorls around the white shell (Fig. 1).

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Lipids Of Fungal Spores, Identification And Metabolism, Jim L. Bushnell Aug 1972

Lipids Of Fungal Spores, Identification And Metabolism, Jim L. Bushnell

Theses and Dissertations

The lipids of the spores of the Basidiomycetes: Ustilago bullata, Lycoperdon perlatum and Calvatia gigantea were investigated. The spores of U. bullata were found to have hydrocarbons ranging from C_9 to C_24, methyl esters of fatty acids ranging from C_14 to C_24, and free fatty acids from C_14 to C_24. The spores of L. perlatum were found to have few hydrocarbons (C_22 being the predominent one); no methyl esters were detected and the fatty acids were from C_15 to C_18. Long chain aldehydes (C_30) were also detected in low concentration. At the ultrastructural level the Lycoperdon spores were found to …

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A Revision Of The Genus Sphaeralcea (Malvaceae) For The State Of Utah, Jane Ardis Murray Jefferies Aug 1972

A Revision Of The Genus Sphaeralcea (Malvaceae) For The State Of Utah, Jane Ardis Murray Jefferies

Theses and Dissertations

It is the attempt of the present writer to present a concise picture of the genus Sphaeralcea as it occurs in the state. Descriptions, a specific key, distribution maps, illustrations and pertinent synonomy are presented.

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Laboratory Rearing, Development And Cytogenetics Of Orchopeas Leucopus (Baker), Robert Francis Allen Aug 1972

Laboratory Rearing, Development And Cytogenetics Of Orchopeas Leucopus (Baker), Robert Francis Allen

Theses and Dissertations

Vector control is fundamental to the suppression and/or eradication of many endemic and epidemic diseases affecting man. The discovery and widespread application of insecticides in vector control programs focused early attention on studies revealing ecological and behavioral characteristics of arthropod vectors. As a consequence of this emphasis, few attempts were made to investigate arthropod cytogenetics. However, recent recognition of the deleterious effects of highly persistent insecticides on the environment and the development of insecticide resistance by vectors of human disease have established the importance of cytogenetics as a base on which programs for control of vector populations may be built …

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Raptor Predation On Pocket Gopher Populations By The Use Of Hunting Perches, Robert C. Christensen Aug 1972

Raptor Predation On Pocket Gopher Populations By The Use Of Hunting Perches, Robert C. Christensen

Theses and Dissertations

The Northern Pocket Gopher (Thomomyst alpoides) is common on open range lands at high altitudes, and range management personnel have long been confronted with the problem of controlling gopher populations. Although some studies indicate that pocket gophers have little or no injurious effects on range in good condition, other studies show that large populations of these animals can seriously damage seeded ranges and ranges in poor condition (Colorado State University Exp, Stat., 1960). Julander, Low, and Morris (1969) indicate that in areas where gophers have reached populations of 27-39 gophers per acre, forage removal by gophers may be from 4.75 …

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Characterization Of Field Populations Of Magarites Pupillus (Gould) (Gastropoda, Prosobranchia), Stephen Craig Schroeter Jul 1972

Characterization Of Field Populations Of Magarites Pupillus (Gould) (Gastropoda, Prosobranchia), Stephen Craig Schroeter

Theses and Dissertations

Field populations of Margarites pupillus (Gould), a numerically abundant prosobranch mollusc occuring on rocky shores in Puget Sound, Washington, have previously received little autecological attention. Seawater table studios and SCUBA observations led to the following conclusions: Populations of Margarites are primarily subtidal. Population density and growth are directly related to algal canopy density. Algal canopy may function in reducing predator efficiency, Margarites populations have a 1:1 sex-reatio and no size dimorphism. Sexually mature individuals live for at least two years, and possibly more than four years.

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Helminths Of Sceloporus Lizards In The Great Basin And Upper Colorado Plateau Of Utah, Richard Carlyle Pearce Jul 1972

Helminths Of Sceloporus Lizards In The Great Basin And Upper Colorado Plateau Of Utah, Richard Carlyle Pearce

Theses and Dissertations

This study was prompted by the scarcity of information on helminths in Sceloporus lizards of Utah. It reports these worms and includes references to parasites of reptiles in the appendix. A microscopic examination of the coelom, mesenteries, liver, lungs, esophagus, stomach, and intestines of 55 lizards was made, but helminths were recovered only from stomachs and intestines. Examination of S. graciosus yielded Opchoristica scelopori, a cestode found in the duodenum, and Cyrtosomum penneri, C. readi, and C. heynemani, three nematodes of the cecum. The latter two are new nematodes for this host species. Examination of S. undulatus yielded three new …

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The Effects Of Temperatures And Chemicals On The Oocysts Of Eimeria Stiedae, Charles Larry Keehner Jul 1972

The Effects Of Temperatures And Chemicals On The Oocysts Of Eimeria Stiedae, Charles Larry Keehner

Theses and Dissertations

A study was made of the effects of temperatures and chemicals on the unsporulated and sporulated oocysts of Eimeria stiedae. In general, oocysts were affected by temperatures lower than -10 C and above +39 C, while normal development occurred between these temperatures. Unsporulated oocysts were more tolerant to temperature extremes, as they survived up to 8 days at 39 C and 12 days at -28 C. Sporulated oocysts were killed after 24 hours storage at 39 C and 4 days at -28 C. Oocyst resistance to low temperatures was not improved if unsporulated and sporulated oocysts were conditioned before and …

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The Boraginaceae Of Utah, Larry C. Higgins Jul 1972

The Boraginaceae Of Utah, Larry C. Higgins

Brigham Young University Science Bulletin, Biological Series

This paper presents a revision of the family Boraginaceae for the state of Utah. Ninety-three species in seventeen genera are recognized. The treatment includes keys, synonymy, descriptions, and citations of representative specimens found in the various herbaria in the state of Utah. The new combination Lappula occidentalis (Wats.) Greene var. cupulata (Gray) Higgins is presented.

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End Matter, Vol. 16 No. 3 Jul 1972

End Matter, Vol. 16 No. 3

Brigham Young University Science Bulletin, Biological Series

No abstract provided.

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Front Matter, Vol. 16 No. 3 Jul 1972

Front Matter, Vol. 16 No. 3

Brigham Young University Science Bulletin, Biological Series

No abstract provided.

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Vegetation Zones Around A Small Pond In The White Mountains Of Arizona, B. Ira Judd Jun 1972

Vegetation Zones Around A Small Pond In The White Mountains Of Arizona, B. Ira Judd

Great Basin Naturalist

Because of a previous study of wet meadows, an investigation of Carnero Lake, White Mountains of Arizona, which is ecologically advancing toward a wet meadow, was undertaken. Information on eutrophication and successional patterns in ponds of the ponderosa pine is needed for better understanding of that ecosystem. Aerial infrared photographs were taken to delineate areas containing aquatic vegetation and as an aid in identifying zones around the pond. Five zones from open water to ponderosa pine were found. Abundance of vegetation by species was estimated in each zone. Protein analyses are given for 29 of the 32 species listed.

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End Matter, Vol. 16 No. 1 May 1972

End Matter, Vol. 16 No. 1

Brigham Young University Science Bulletin, Biological Series

No abstract provided.

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Front Matter, Vol. 16 No. 1 May 1972

Front Matter, Vol. 16 No. 1

Brigham Young University Science Bulletin, Biological Series

No abstract provided.

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The Hyobranchium And Throat Myology Of The Adult Ambystomidae Of The United States And Northern Mexico, John E. Krogh, Wilmer W. Tanner May 1972

The Hyobranchium And Throat Myology Of The Adult Ambystomidae Of The United States And Northern Mexico, John E. Krogh, Wilmer W. Tanner

Brigham Young University Science Bulletin, Biological Series

The 16 species and subspecies of the Ambystomidae of the United States are placed into six groups according to their throat morphology as follows: The Dicamptodon group, the Rhyacotriton group, the A. Annulatum–A. cingulatum group, the A. gracile-A. jeffersonianum-A. mabeei-A. macrodactylum-A. maculatum group, the A. talpoideum group, the A. opacum-A. texanum group, and the A. rosaceum-A. t. tigrinum-A. t. melanostictum-A. t. nebulosum group. Dicamptodon appears to be the most primitive group and Rhyacotriton the most specialized. Based on the morphology of the throat region it is suggested that A. rosaceum be placed in the tiger salamander group as a subspecies …

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Three New Species Of Petrified Wood From The Upper Jurassic Morrison Formation Of Southern Utah, David Arthur Medlyn May 1972

Three New Species Of Petrified Wood From The Upper Jurassic Morrison Formation Of Southern Utah, David Arthur Medlyn

Theses and Dissertations

The petrified wood for this study was collected from the Upper Jurassic Morrison Formation in the south central part of Utah on the Colorado Plateau. The study area, located near Clay Point, Garfield County, Utah, is south of the Henry Mountains. The site is relatively undisturbed containing many well preserved specimens. This study constitutes the first detailed study of fossil coniferous woods of the Morrison Formation. Although this formation contains abundant petrified wood, its floral composition has been virtually unknown. Three genera have been identified in this study: Protopiceoxylon Gothan, Mesembrioxylon Seward, and Taxaceoxylon (Unger) Krausel. Protopiceoxylon has only been …

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The Reproductive Biology Of The Leech Helobdella Stagnalis (Linnaeus) In Utah Lake, David L. Tillman May 1972

The Reproductive Biology Of The Leech Helobdella Stagnalis (Linnaeus) In Utah Lake, David L. Tillman

Theses and Dissertations

The reproductive biology of the brooding leech Helobdella stagnalis (Linnaeus) in Utah Lake was studied for an 18 month period from June 1970 to December 1971. In determining the annual reproductive cycle, the number of adult leeches carrying eggs or young were counted at weekly intervals during the reproductive season and monthly during the rest of the year. Gonadal staging data from histological sections were correlated with the field collection data. It was found that two broods of young were produced by the adult animals during the reproductive season. Continuous water temperatures were recorded at the study site throughout the …

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Vegetation Changes Following Fire In The Pinyon-Juniper Type Of West Central Utah, Milo Arnel Barney May 1972

Vegetation Changes Following Fire In The Pinyon-Juniper Type Of West Central Utah, Milo Arnel Barney

Theses and Dissertations

A total of 28 burn areas, that varied in age from 3-100+- years, were analyzed in a study of succession following fire, in the pin yon-juniper woodlands of west central Utah. Data were collected by means of the line-point and quadrat methods. These data were subjected to a multiple regression analysis. Canopy cover, basal area (sq. ft./acre) and density (trees/acre) of juniper were highly correlated with age of burn. Percentage dead sagebrush was found to be positively correlated with density of junipers. The stages of succession following fire began with weedy annuals, that reached a peak within 3-4 years. Juniper …

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A Taxonomic Study Of The Western Collared Lizard (Crotaphytus Collaris), Nathan M. Smith May 1972

A Taxonomic Study Of The Western Collared Lizard (Crotaphytus Collaris), Nathan M. Smith

Theses and Dissertations

The marked pattern and coloration which distinguish members of Crotaphytus collaris baileyi in its western range indicated a need to compare it to the collaris-complex consisting of C.c. auriceps, C.c. baileyi, and C.c. fuscus. Thirty-two external and sixteen cranial characters were measured on preserved specimens. Blood serum proteins were compared by disc gel electrophoresis. Cluster, canonical, and discriminant analyses were used to define population characteristics and areas of intergradation. Disc electrophoresis did not reveal consistent population differences. The western range of C.c. baileyi is restricted to Central Arizona. The Great Basin form from western Arizona, western Utah, southern Idaho, southeastern …

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The Bottom Fauna Of Fish Lake, Utah And Its Relationship To The Trout Fishery, Dennis L. Shirley Apr 1972

The Bottom Fauna Of Fish Lake, Utah And Its Relationship To The Trout Fishery, Dennis L. Shirley

Theses and Dissertations

One-hundred and three bottom samples taken at Fish Lake, Utah from July, 1969 to June, 1970 were analyzed to determine the abundance, distribution, and standing crop of the bottom fauna species and to relate their availability to the amount of food eaten by the trout. Twenty-three taxa, representing three phyla and 19 families were collected. An amphipod, Gammarus limnaeus, in the littoral zone, and a tubificid worm, Rhyacodrilus coccineus, in the sublittoral and profundal zones, were the most abundant species. All 23 species were unevenly distributed in the littoral zone, whereas, only eight were found in the sublittoral and five …

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Analysis Of Asexual Reproduction Dugesia Dorotocephala, Harvey Dee Mecham Apr 1972

Analysis Of Asexual Reproduction Dugesia Dorotocephala, Harvey Dee Mecham

Theses and Dissertations

Genetic control of decapitation-induced fission in planaria is mediated by stimulator and inhibitor molecules. Resolution of the two factors was accomplished by filtration chromatography of whole planaria extract. The stimulator (M.W. 2500 to 3500) was purified with ion exchange chromatography and increases the multiple fission rate. The inhibitor (M.W. 20,000 to 50,000) is non-dialyzable, heat labile and is inactivated unless kept frozen. Storage at 4°C results in a loss of inhibitory capacity with a concomitant stimulator increase, suggesting a protein-stimulator complex as the inhibitor. In light of a demonstrated animal intercommunication system, the inhibitor-stimulator complex is hypothesized as part of …

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Nesting Of The White-Faced Ibis (Plegadis Chihi) Of Utah Lake, Kenichi David Kaneko Apr 1972

Nesting Of The White-Faced Ibis (Plegadis Chihi) Of Utah Lake, Kenichi David Kaneko

Theses and Dissertations

Information on the nesting of the White-faced Ibis (Plegadis chihi) in Utah County is presented for the first time. Nests built in hardstem bulrush (Sciprus acutus) settled from an average height of 120.8cm on June 9 to 93.6cm on June 27, 1971. Nest spacing ranged from 2m to 9m, averaging 4.6m. Invertebrates of the class Arachnida and the insect orders Coleoptera, Homoptera, Lepidoptera, and Thysanoptera were collected in a Berlese funnel. Average clutch size was 3.17. Egg length and width averaged 51.40mm X 36.75mm. Average volume was 36.93cc. In 21 study nests, 45.8 percent of the eggs hatched, beginning on …

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Front Matter, Vol. 16 No. 2 Apr 1972

Front Matter, Vol. 16 No. 2

Brigham Young University Science Bulletin, Biological Series

No abstract provided.

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