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The Genera Of Asteraceae Endemic To Mexico And Adjacent Regions, Jose Luis Villaseñor

Aliso: A Journal of Systematic and Floristic Botany

The flora of Mexico includes about 119 endemic or nearly endemic genera of Asteraceae. In this study, the genera are listed and their distribution patterns among the floristic provinces of Mexico analyzed. Results indicate strong affinities of the endemic genera for mountainous and arid or semiarid regions. Since its first appearance in Mexico, the Asteraceae diversified into these kinds of habitats, which were produced mostly by recurrent orogenic and climatic phenomena. The specialized tribes Heliantheae and Eupatorieae are richly represented, a fact that places Mexico as an important secondary center of diversification for the Asteraceae.

Evolutionary Aspects Of Reptilian And Mammalian Enamel Structure, A. Sahni

Scanning Microscopy

The evolution of enamel structure is dealt with here on the basis of fossil reptiles and mammals ranging from the Triassic to the present. The evidence suggests that prismatic enamel had developed in some therapsid reptiles and the mammal, Eozostrodon about 180 million years ago. For the next 100 million years, mammalian evolutionary history is sparingly documented and this is reflected in the poor record of enamel evolution during this period. The few Jurassic reptiles and mammals studied suggest a pre-prismatic structure. In the Late Cretaceous (BO to 65 million years ago) when the fossil record improves, mammalian enamel investigated …

High Resolution Scanning Auger Microscopy Of Mineral Surfaces, M. F. Hochella Jr., A. M. Turner, D. W. Harris

Scanning Electron Microscopy

There are a number of cases where scanning Auger microscopy can be used to determine the near-surface composition of minerals with extremely high lateral resolution. This involves collecting Auger spectra with reasonable signal to noise ratios without encountering significant beam induced charging or surface degradation, even if the beam is impinging on a grain less than 1μm in diameter. We typically use a 3 keV beam with less than 10 nA beam current on a sample surface that is tilted (to increase backscattered and secondary electron emission efficiency) and relatively flat. To further minimize surface degradation, vacuum levels are kept …

Metabolic Activity Of The Epiphytic Community Associated With Spartina Alterniflora, Wilmer C. Stowe, James G. Gosselink

Gulf and Caribbean Research

Primary production and respiration rates were determined for two epiphytic communities associated with Spartina alternifloraLoisel., in the southwestern Barataria Bay area of Louisiana. The communities studied were: (1) a shoreline community and (2) a community 1.5 meters inland from the shoreline site. Annual mean net production and respiration rates for the shoreline community were 25.8 and -19.6 mg C • (m² substrate area)^-1 • h^-1 respectively;whereas the inland community showed corresponding rates of -3.3 and -12.5 mg C • (m² substrate area)^-1 • h^-1, respectively. Thus, the shoreline community was a net …

Developments In Federal Water Policies And Programs, Harold W. Furman Ii

The Federal Impact on State Water Rights (Summer Conference, June 11-13)

14 pages.

Program Abstracts, 96th Session, Iowa Academy Of Science, April 27-28 1984, Iowa Academy Of Science

Iowa Academy of Science Documents

Presentation abstracts from the annual meeting of the Iowa Academy of Science

Farm, Ranch And Home Quarterly Institute Of Agriculture And Natural Resources, University Of Nebraska- Lincoln

Farm, Ranch and Home Quarterly

In this issue:

A Message from the Vice Chancellor................ 2

Needling Makes Beef More Tender .......................... 3

Detecting Herbicide Carryover in Soil ........................ 4

Roadside Marketing........................... 6

Many Uses Found for Geologic Maps ........................ 8

Nebraska Moves Ahead .................................... 10

Resistant Alfalfa Varieties Sought by Researchers ................................ 12

Kids Having Kids ................................... 14

Psuedorabies Virus Causes Producers Severe Losses ........................... 16

Corn or Grain Sorghum? ................................... 19

Don't Fool-Cooperate with Mother Nature ........................ 21

Sulfur Can Boost Corn Yields on Sandy Soils ........................... 23

A Seasonal Study Of Phytoplankton Composition Abundance And Productivity In Back Bay, Virginia, Robert Ringgold Comegys

Biological Sciences Theses & Dissertations

Phytoplankton samples were collected monthly (August 1974-June 1975) at two stations in the Back Bay system of southeastern Virginia. Measurements of phytoplankton productivity and potentially influencing environmental parameters (water and air temperature, turbidity, depth, pH, salinity, dissolved oxygen) accompanied sample collections. A total of 106 phytoplankton species, representing six algal divisions and 54 genera were identified. Cyanophyta species were dominant at both stations in the warmer months of August, September, October, and June, and in April at one station only. In all remaining months, Chlorophyta species were dominant, indicating a seasonal shift in phytoplankton composition during winter and spring. The …

Location Of The Mississippi Sound Oyster Reefs As Related To Salinity Of Bottom Waters During 1973-1975, Charles K. Eleuterius

Gulf and Caribbean Research

The relationship of producing natural oyster reefs of Mississippi Sound to the salinity regime of bottom waters is investigated. Extreme and average conditions were extracted from data taken at 87 stations over a 21-month period from June 1973 through February 1975. With one exception, the producing reefs were subjected to salinity minimums of 2.0 to 4.0 parts per thousand (ppt), maximums of 18.0 to 22.0 ppt, with average conditions being between 10.0 and 16.0 ppt. Salinity-suitable areas in the Sound not now inhabited by oysters are described.

The Population Dynamics Of Tanypus Stellatus Coquillett (Diptera: Chironomidae) In Goshen Bay Of Utah Lake, Dennis Kenji Shiozawa

Theses and Dissertations

The population dynamics of Tanypus stellatus in Goshen Bay of Utah Lake was investigated from July 18, 1973, to August 5, 1974. Samples were collected from three stations with an Ekman grab and a K-B corer. The samples were washed in a 110 micron nitex screen and then floated in a sucrose solution. The K-B core was used to determine the vertical distribution of Tanypus stellatus. Ninety-six percent of the Tanypus stellatus larvae are located in the top five centimeters; 99 percent are less than ten centimeters deep. The Ekman grab was used to study the population dynamics of the …

Inventory Of Lake Studies In Maine, Charles F. Wallace Jr., James M. Strunk

Maine Collection

Inventory of Lake Studies in Maine

By Charles F. Wallace, Jr. and James M. Strunk

State Planning Office, Water Resources Planning Division, July 1973.

"Printed under Appropriation Number 4248.5 and financially assisted by planning grants from the United States Water Resources Council Title III funds."

Contents: Introduction / Investigating Agencies / Federal Agencies / State Agencies / Regional Planning Commissions and Economic Development Districts / Maine Colleges and Universities / Private / Other Private / Other / Appendices

A Quarter Century Of Geology At The Gulf Coast Research Laboratory (1948-1973), Ervin G. Otvos Jr.

Gulf and Caribbean Research

Overview of the history of geology courses and research at the Gulf Coast Research Laboratory in Ocean Springs, Mississippi.

A Flora From The Dakota Sandstone Formation Near Westwater, Grand County, Utah, Samuel R. Rushforth

Theses and Dissertations

A cretaceous (Cenomanian) flora from the Dakota Sandstone Formation near Westwater, Grand County, Utah contains an admixture of ferns and angiosperms. The ferns of this flora are representative of an older Jurassic-Wealden vegetational type, whereas the angiosperms are typical of the modern vegetational type. Species of Gleichenia and Matonidium and Astralopteris coloradica represent the dominant forms in this flora. The Westwater flora contains fourteen genera including nineteen species and one variety. New species described from this flora include Asplenium dakotensis, Coniopteris westwaterensis and Ilex serrata.

The Evolution Of Parasitism Among Bees, George E. Bohart

Faculty Honor Lectures

Before discussing parasitic bees, I will present a rough outline of the biology of "ordinary" or non-parasitic bees. The superfamily Apoidea (bees) includes perhaps 25,000 or 30,000 species divided into nine families by recent authorities (Stephen, Bohart, Torchio, 1969) . A common biological thread holding this vast assemblage together is the provision by adults of pollen and nectar for their young. Only in the honey bees (the genus Apis which includes four species) are the larvae fed primarily on a different substance (a secretion of the pharyngeal glands) , and even this is derived from pollen and honey eaten by …

The Evolution Of Parasitism Among Bees, George E. Bohart

All PIRU Publications

No abstract provided.

Proceedings Of The Arkansas Academy Of Science - Volume 24 1970, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

Aggressive Man And Aggressive Beast, Allen W. Stokes

Faculty Honor Lectures

Whether man can live in harmeny with his environment depends in great measure en his ability to' live with his fellew man. Can man learn to' engineer human seciety in time to' prevent a helecaust? Mere specifically, can we learn to' prevent aggressien er to' channel it harmlessly? The ethelegist leeks upen man's behavier as just part ef the tetal spectrum ef animal behavier. Therefere, much of what we learn abeut the behavier ef lewer animals sheuld relate to' human behavier.

Aggressien is in the headlines every day, and in the past few years there has been a 'Steady stream …

An Ecological Study Of Waterfowl Habitat At Powell's Slough, Utah Lake, Bruce I. Barnett

Theses and Dissertations

This study attempts to give a preliminary survey of the marsh habitat in Powell's Slough near Utah Lake. The following aspects are treated: seasonal waterfowl utilization of the slough, productivity of nesting water-fowl, description of the vegetation, invertebrate analysis, and analysis of environmental factors that may influence the habitat.

The Brule-Gering (Oligocene-Miocene) Contact In The Wildcat Ridge Area Of Western Nebraska, C. Bertrand Schultz, Charles H. Falkenbach, Carl F. Vondra

Bulletin of the University of Nebraska State Museum (1924–2023)

The contact between the Brule Formation (Oligocene) and the Gering Formation (Miocene) can be readily distinguished in the Wildcat Ridge area, as elsewhere in western Nebraska. At the critical fossiliferous exposures at Castle Rock in Scotts Bluff County, the contact on the south face between the two formations is defined as 129 feet above the base of the "Upper Ash" bed, which corresponds to the upper portion of Darton's (1899, PI. C, Fig. D, following p. 754) "sandy phase" in the upper part of the Brule. Certain key beds in the Gering Formation can be traced laterally from a channel …

A Microscopic Study Of An Early Pennsylvanian Flora From The Manning Canyon Shale, Utah, Max W. Blaylock

Theses and Dissertations

The Manning Canyon Shale on the eastern slope of Lake Mountain in Utah County, Utah contains an Early Pennsylvanian flora within its upper shales. Many of these fossils appear to be new species. A microscopic study of the tissue remains can be of value in the further classification of these fossils. Selected fossils were macerated in hydrofluoric acid, and the residues were examined microscopically for tissue remains. Objects identified as fossil tissue remains were found in twenty five of the forty-eight specimens examined. Fibers, fiber tracheids, tracheids, and spores were isolated from fossils identified as Calamites. The spores were possibly …

Available Water Supply Of The Las Vegas Ground-Water Basin Nevada, Glenn Thomas Malmberg

Publications (WR)

The Las Vegas ground-water basin as described in this report includes the southern part of Indian Spring Valley, Three Lakes Valley, the northern half of Ivanpah Valley, and Las Vegas Valley. These valleys in part are inferred to form a hydrologic unit that includes an area of about 3,000 square miles in the southern part of Clark County, Nev.

The valleys forming the Las Vegas ground-water basin are broad structural depressions surrounded by mountains. The climate of the region is arid, and precipitation in the basin lowlands rarely exceeds 5 inches per year. Drainage is interior except for occasional Hood …

Second Bibliography And Index For The Philosophy Of Geology, Claude C. Albritton Jr.

Journal of the Graduate Research Center

The body of writings on the philosophy and history of geology has grown in a remarkable way since the end of the Second World War. There is no obvious explanation for this quickening of interest in what are surely the most academic aspects of a science best known for its practical applications. Influences arising both from within and from outside the geological profession have probably been responsible. It is a matter of record that many departments of geology, upon resuming full-time operations after the war, decided not to go on moving in the old curricular ruts. The new courses, even …

The Seventy-Sixth Session Of The Iowa Academy Of Science And The Thirty-Second Convention Of The Iowa Junior Academy Of Science, April 17-18, 1964, Iowa Academy Of Science

Iowa Academy of Science Documents

No abstract provided.

Charophytes Of Pleistocene Age From Delta And Denton Counties, Texas, Harold E. Schlichting Jr.

Journal of the Graduate Research Center

Collections of Chara oogonia from late Pleistocene alluvium beneath the floodplain of the North Fork of the Sulphur River near Ben Franklin (Delta County), and from the second terrace above Clear Creek (Denton County) were studied. The radiocarbon dates of the Sulphur River deposits are 10,000-11,000 B.P., while those of the Clear Creek deposits are about 28,000 B.P.

The Archeology Of The Lime Creek Site In Southwestern Nebraska, E. Mott Davis

University of Nebraska State Museum: Staff and Affiliates, Publications

The Lime Creek site is a stratified Early Lithic (Paleo-Indian) camp site buried in the Terrace-2A alluvial fill of a valley in the dissected loess plains. Geological correlations indicate an early Valders (Wisconsin- IV) date. A radiocarbon date (No. C-471) of 9524 B.P. from just below Lime Creek I, the lowest occupation zone, must be taken only as a minimal possible age for the site. The animal bones in Lime Creek I are primarily of pronghorn and beaver, whereas those in Lime Creek III, the highest occupation zone, are exclusively of bison. The change in hunting patterns seems due to …

Studies In Experimental Evolution, William Sidney Boyle

Faculty Honor Lectures

The Principle of organic evolution is the most fundamental one yet discovered in the sciences concerned with the nature and origin of living things. During the one hundred years which have elapsed since Darwin's explanation of the mechanisms of evolution a great deal has been learned to supplement his theory. Nevertheless, students of evolution universally acknowledge the significance of his profound contributions. The importance of natural selection as a creative force in evolution is inescapable.

The present discussion is chiefly concerned with techniques which the writer has used to accelerate, or at least to manipulate, the evolutionary processes. It may …

Good Nutrition For The Family, Ethelwyn B. Wilcox

Faculty Honor Lectures

A BASIC OBJECTIVE of the Faculty Association of UTAH STATE UNIVERSITY, in the words of its constitution, is to encourage intellectual growth and development of its members by sponsoring and arranging for the publication of two annual faculty lectures in the fields of (a) the biological and exact sciences, including engineering, called the Annual Faculty Honor Lecture in the Natural Sciences; and (b) the humanities and social sciences, including education and business administration, called the Annual Faculty Honor Lecture in the Humanities. The administration of the University is sympathetic with these aims and shares the cost of publishing and distributing …

Utah's Future Water Problems, Wayne D. Criddle

Faculty Honor Lectures

Utah is rapidly changing from what was once predominately an agricultural state to an urban and industrial state. This shift is not decreasing our water needs; it is often intensifying these needs and creating many new problems. Perhaps we should ask ourselves-are we prepared to recognize and accept these changes? Are we really facing up to the problems that are developing or are we turning our heads and hoping they will go away? These changes involve technical, legal, and sociological problems never before encountered, some of which I should like to discuss.

Before attempting to look at Utah's water problems …

Medial Pleistocene Fossil Vertebrate Localities In Nebraska, C. Bertrand Schultz, Lloyd G. Tanner

Bulletin of the University of Nebraska State Museum (1924–2023)

The accurate geologic dating of Pleistocene vertebrate localities which occur outside the glaciated regions has always been difficult. Several new fossil localities in Nebraska now provide data for a better understanding of the paleoecology and faunal evidence of the medial Pleistocene of the Great Plains region.

A fossil quarry, containing the remains of both vertebrates and invertebrates, has been discovered in south-central Nebraska (11/2 miles south and west of Angus in Nuckolls County). The fossils are preserved in Sappa silts in a lime concentration zone (C horizon) of a Yarmouth paleosol. The calcium carbonate appears to have been responsible for …

Range Liverstock Nutrition And Its Importance In The Intermountain Region, C. Wayne Cook

Faculty Honor Lectures

It has been estimated that about 728 million acres or about 76 percent of the entire land area in the West is used for grazing (Stoddard and Smith 1956). In Utah about 93 percent of the land area or 48,900,000 acres is considered range land (Reuss and Blanch 1951). Although some of this range land is forested, a large area of it can be used only for grazing. Therefore, range livestock production is an important segment of western agriculture.

Before 19'00 most of the animals in the West grazed on the range all year. However, irrigation crop production has expanded …