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Fishes Of Sylamore Creek, Stone County, Arkansas, George C. Frazier, John K. Beadles Jan 1977

Fishes Of Sylamore Creek, Stone County, Arkansas, George C. Frazier, John K. Beadles

Journal of the Arkansas Academy of Science

A survey of the fishes of Sylamore Creek in northcentral Arkansas yielded a total of 15,041 specimens representing 44 species, including one hybrid, distributed among 11 families. The three most abundant fishes collected were: Notropis pilsbryi Fowler, Dionda nubila (Forbes), and Notropis telescopus (Cope), respectively. Two species, Campostoma anomalum pullum (Agassiz), and N. pilsbryi, were collected at every station. Sylamore Creek is a clear predominantely spring-fed stream that originate in the Ozark Mountains of northcentral Arkansas and empties into the White River 72.3 km above Bates vilie. Sylamore Creek is composed of two branches, North and South Sylamore, which comprise …


Forest Communities Of Crowley's Ridge, G. Thomas Clark Jan 1977

Forest Communities Of Crowley's Ridge, G. Thomas Clark

Journal of the Arkansas Academy of Science

The forest communities of Crowley's Ridge in Arkansas were surveyed by sampling 22 selected stands which met predetermined criteria. The Importance Value (I.V.) for each woody species over one decimeter, diameter breast height (dbh), was derived from the combined values of relative density, relative dominance by basal area (B.A.), and relative frequency. Young trees under one decimeter, dbh, were assigned to three height classes from which frequency, density, and stratification data were derived. White Oak-Red Oak-Hickory is the general forest type. Its subdivisions: Oak-Hickory-Pine Forest, Mixed Oak-Hickory Forest, and White Oak-Beech Forest are advocated for practical field references. They are …


Comparative Studies Of The Witch Hazels Hamamelis Virginiana And H. Vernalis, Jack L. Bradford, Daniel L. Marsh Jan 1977

Comparative Studies Of The Witch Hazels Hamamelis Virginiana And H. Vernalis, Jack L. Bradford, Daniel L. Marsh

Journal of the Arkansas Academy of Science

An investigation of Hamamelis vernalis Sarg. and H. Virginiana L. was begun in southwestern Arkansas in the tall of 1976. An overlap of flowering periods occurred from late November through December, affording the possibility of hybridization. At one site the two taxa flowered simultaneously only 30 yards apart. Variation occurs in both taxa and there is a degree of overlap in most characters, but the composite of diagnostic features distinguishes the two species. The hybrid origin of H. vernalis suggested by Jenne (1966) does not seem likely.


Development Of Sporangia In Polypodium Aureum Var. Undulatum: Initial Scanning Electron Microscopial Observations, William R. Bowen, David Williams Jan 1977

Development Of Sporangia In Polypodium Aureum Var. Undulatum: Initial Scanning Electron Microscopial Observations, William R. Bowen, David Williams

Journal of the Arkansas Academy of Science

Preliminary SEM observations of developing sori of P. aureum revealed several potential areas for future ultrastructural (SEM and TEM) study, including ontogeny of sporangial initials, annulus differentiation, and sport wall development.


Fishes Of Randolph County, Arkansas, Steve M. Bounds, John K. Beadles, Billy M. Johnson Jan 1977

Fishes Of Randolph County, Arkansas, Steve M. Bounds, John K. Beadles, Billy M. Johnson

Journal of the Arkansas Academy of Science

A survey of the fishes of Randolph County in northcentral Arkansas was made between June 1973 and March 1977. Field collections, literature records, and museum specimens revealed the ichthyofauna of Randolph County to be composed of 128 species distributed among 24 families. Cyprinidae was the largest family, being represented by 34 species while Percidae was represented by 24 species. Randolph County is composed of Ozark Uplands and Coastal Plain areas. All of the stream systems flow into the Black River system with the exception of Village Creek in the southeastern corner of the county which flows into White River. The …


Yolk-Periblast Junction In Fundulus Heteroclitus, Claudia F. Bailey Jan 1977

Yolk-Periblast Junction In Fundulus Heteroclitus, Claudia F. Bailey

Journal of the Arkansas Academy of Science

The yolk of teleost eggs becomes covered with a syncytial periblast during embryonic development. Nutrients must be transported through the periblast before they are available to the embryo. Tranmission electron micrographs of thin sections and of freeze-fractured replicas show a number of features at the yolk-periblast junction which may be correlated with yolk transport. These features include vesicle formation and exchange, channelization and interdigitation.


Oxygen Toxicity In The Mammalian Liver, Dennis A. Baeyens, M. J. Meier Jan 1977

Oxygen Toxicity In The Mammalian Liver, Dennis A. Baeyens, M. J. Meier

Journal of the Arkansas Academy of Science

The effect of hyperbaric oxygen tensions on the oxygen consumption of mouse liver homogenates was investigated. It was found that hyperbaric oxygen rapidly inhibits the oxidative metabolism of the mammalian liver. Mouse liver homogenate exposed to an oxygen tension of 3837.8 mm Hg for 30 minutes demonstrated a 50.6% reduction in oxygen consumption compared to controls exposed to nitrogen at ambient pressure. The effects of reduced glutathione as a protective agent against hyperbaric oxygen toxicity were also examined. Liver homogenates pretreated with reduced glutathione and exposed to hyperbaric oxygen tensions demonstrated greater activity than untreated controls. It is concluded that: …


Scaled Chrysophyceae From Arkansas, Robert A. Andersen, Richard L. Meyer Jan 1977

Scaled Chrysophyceae From Arkansas, Robert A. Andersen, Richard L. Meyer

Journal of the Arkansas Academy of Science

An initial study of scaled chrysophytes from Arkansas is presented. Species include: Synura Petersenii f. Petersenii, S. spinosa f. spinosa, S. curtispina f. curtispina, S. curtispina f. reticulata, S. uvella, Mallomonas striata var. striata, M. pumilio var. pumilio, and Chrysosphaerella brevispina. Transmission electron micrographs of their siliceous scales are included.


Brachiopods From The Caribbean Sea And Adjacent Waters, Arthur G. Cooper Jan 1977

Brachiopods From The Caribbean Sea And Adjacent Waters, Arthur G. Cooper

Studies in Tropical Oceanography

No abstract provided.


Towards Integrated Protection From The Southern Pine Beetle, Jack E. Coster Jan 1977

Towards Integrated Protection From The Southern Pine Beetle, Jack E. Coster

Faculty Publications

Current southern pine beetle ( Dendroctonus frontalis Zimm.) control depends heavily upon direct approaches having short-term payoffs. Chemical or physical tactics have fidled to check epidemics in the Gulf South. A major challenge lies in developing and using indirect methods for managing this pest. Promotion of stand resistance and biotic agents, and manipulation of stand density and cutting practices, hold prospect for reducing the incidence and severity of beetle-caused losses.


Farm, Ranch And Home Quarterly Institute Of Agriculture And Natural Resources, University Of Nebraska- Lincoln Jan 1977

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

Farm, Ranch and Home Quarterly

In this issue: 2 A Message from the Vice Chancellor

3 Research Returns Tip the Scales

5 Herbicides-Broadcast or Band?

7 Ag Students: The Changing Profile

8 Infant Diets Studied with Mothers' Help

10 Machinery Trading and Taxes

12 Trees for Profit

14 "Dairy Store" Serves Students, Staff and Stomachs

16 Irradiation Holds Potential for Nebraska 1

8 Back to the Farm

20 Fire at Pine Ridge

23 Farmers Keep Tabs on Energy


The Intestinal Platyhelminths Of Southwestern And Central West Virginia Amphibia And Relationships Between The Degree Of Infestation And Habitat Of Amphibians And Sex Of Host, Stanley B. Mills Jan 1977

The Intestinal Platyhelminths Of Southwestern And Central West Virginia Amphibia And Relationships Between The Degree Of Infestation And Habitat Of Amphibians And Sex Of Host, Stanley B. Mills

Theses, Dissertations and Capstones

In April and May, 1977, 397 (14 species) amphibians were collected from southwestern and central West Virginia and examined for parasites. Five species of trematodes and two species of cestodes were found from 93 hosts. The total of 397 amphibians was subdivided, for convenience, into six categories of amphibians; aquatic male and female, terrestro-aquatic male and female, and terrestrial male and female. Nine of 24 (37.5%). female aquatic amphibians was the highest incidence found, while terrestro-aquatic females contained the highest mean number (6.0) worms per incidence, and parasite loads of host. Hosts, each platyhelminth specimen are given.


Pollen Of The Myricaceae - A Preliminary Report, Marshall D. Sundberg Jan 1977

Pollen Of The Myricaceae - A Preliminary Report, Marshall D. Sundberg

Journal of the Minnesota Academy of Science

Pollen of 16 species and one variety of the Myricaceae was examined, including members of each of the genera proposed by Chevalier (1901) in addition to Canacomyrica (Guillaumin, 1939). Comparison of pollen characters within genera, within sections, between sections, and between genera suggests that the Myricaceae can be divided into four genera: Canacomyrica; Comptonia; Gale; and Myrica. The genus Myrica can be further divided into three sections; Cerophora, Fava, and Morella.


Mammals Of Southwestern Minnesota, Carl H. Ernst, Lee French Jan 1977

Mammals Of Southwestern Minnesota, Carl H. Ernst, Lee French

Journal of the Minnesota Academy of Science

Ranges of the 45 wild mammals occuring in southwestern Minnesota are discussed and documented. Eight other species that either formerly occurred in the area or might exist but have not yet been documented also are considered. Seven species are recorded from southwestern Minnesota for the first time: Scalopus aquaticus, Myotis keenii, Lasionycteris noctivagans, Marmota monax, Spermophilus franklinii, Tamiasciurus hudsonicus, and Rattus norvegicus.


Revised Distribution Records Of Some Minnesota Fishes, Craig P. Anderson, James E. Erickson, Jon Ross, James C. Undershill Jan 1977

Revised Distribution Records Of Some Minnesota Fishes, Craig P. Anderson, James E. Erickson, Jon Ross, James C. Undershill

Journal of the Minnesota Academy of Science

Recent collections of fishes from Minnesota have resulted in the addition of one species, Fundulus sciadicus (Cyprinodontidae), to the state's inland faunal list. Additional information on the distribution of 12 other species (Notropis topeka, Notropis spilooterus, Ictiobus byprinellus, Carpiodes byprinus, Moxostoma valenciennesi, Notorus flavus, Morone chrysops, Lepomis megalotis, Stizostedion canadense, Percina shumardi, Etheostoma caeruleum, and Cottus bairdi) is presented. These new records are the result of field work in the Missouri River, Red River, and Lake Superior drainage systems of Minnesota.


Impact Of Dog Predation On Minnesota Whitetail Deer, Terry John Kreeger Jan 1977

Impact Of Dog Predation On Minnesota Whitetail Deer, Terry John Kreeger

Journal of the Minnesota Academy of Science

A survey was conducted among conservation officers in Minnesota to investigate predation by dogs (Canis familiaris) on the whitetail deer (Odocoileus virginianus) and the distribution of dog-killed deer within the state. Of the 124 conservation officers checked, 95 confirmed 407 deer killed by dogs from April 1, 1975, through March 31, 1976. Officers also received 1,483 complaints of dogs chasing deer and 626 dogs were destroyed in this activity. Ninety-four percent of these dogs were thought to be domestic, as opposed to feral. The effects of long-distance chases of deer by dogs, prey selectivity and the profile of the free-roaming …


Phytoplankton Production In A Lake With A Metalimnetic Oxygen Maximum, David Z. Gerhart Jan 1977

Phytoplankton Production In A Lake With A Metalimnetic Oxygen Maximum, David Z. Gerhart

Journal of the Minnesota Academy of Science

Carbon-14 production measurements and chlorophyll profiles are presented for a lake with a metalimnetic production maximum. Annual phytoplankton production is estimated as 50 g Cim year. Lakes of this type are quite common yet present difficulties in classifying lakes by production measurements and in using infrequent measurements to infer temporal trends in productivity. The results of two different liquid scintillation methods are compared, and data are presented which suggest that counting efficiencies may be reliably determined in Aquasol, a xylene based fluor, by either the internal standard or channels ratio techniques.


Presettlement Vegetation Of The Nemadji River Basin, Rudy G. Koch, Larry A. Kapustka, Lorraine M. Koch Jan 1977

Presettlement Vegetation Of The Nemadji River Basin, Rudy G. Koch, Larry A. Kapustka, Lorraine M. Koch

Journal of the Minnesota Academy of Science

Features of presettlement vegetation of the Nemadji River watershed were determined from surveying records covering three counties in two states. Data from 3,346 trees indicated major distributional differences in portions of the watershed. White pine (Pinus strobus L.) was the predominant species of the Glacial Lake Duluth Basin, while Tamarack (Larix laricina (Du Roi, K. Koch) characterized the surrounding area of glacial till. In addition, forests occupying ravines were, in general, composed of larger individuals and exhibited less evidence of reproduction than trees in adjacent uplands, which might suggest less erosional disturbance than is evident today.


Partial Sterility In Drosophila Melanogaster: Schemes For Complex Chromosome Rearrangements, Richard V. Kowles, John Richards, Christine Adams, Jeni Lichtenfels, Robert Trauscht, Robert Husfield Jan 1977

Partial Sterility In Drosophila Melanogaster: Schemes For Complex Chromosome Rearrangements, Richard V. Kowles, John Richards, Christine Adams, Jeni Lichtenfels, Robert Trauscht, Robert Husfield

Journal of the Minnesota Academy of Science

These investigations are pilot studies of possible chromosome rearrangements to effect sterility in insects . Techniques of oviposition and partial sterility in Drosophila melanogaster are described. Partial sterility is measured for a number of different crossing combinations using wildtype stocks, heterozygous translocation stocks, and homozygous translocation stocks : the highest percent partial sterility occurring when F-1 intercross translocation stocks are used as one of the parents. Three different crossing schemes to gain more complex chromosome rearrangements and their outcomes are reported, though tests indicated negative results in these . Methods devised to distinguish between simple and complex translocation stocks in …


G77-355 A Guide For The Control Of Flies In Nebraska Feedlots And Dairies (Revised March 1990), John B. Campbell Jan 1977

G77-355 A Guide For The Control Of Flies In Nebraska Feedlots And Dairies (Revised March 1990), John B. Campbell

University of Nebraska-Lincoln Extension: Historical Materials

Flies, especially stable and house flies, can create serious and costly problems for feedlot and dairy operations. This publication describes several methods for control.

Several species of flies may be in confined livestock facilities during summer. The stable and house fly are the most serious pests. Blow flies also may be present if molasses is in the diet. Horn flies--small blood-feeding flies--may be present in early spring. These flies overwinter as pupae in or near manure pats in range or pasture. If cattle are not present in the grassland when horn flies emerge, they will migrate to confinement cattle. Normally, …


Temporal Aspects Of Calling Behavior In Oyster Toadfish, Opsanus-Tau, Michael L. Fine Jan 1977

Temporal Aspects Of Calling Behavior In Oyster Toadfish, Opsanus-Tau, Michael L. Fine

Biology Publications

The oyster toadfish, Opsanus tau (Linnaeus), produces two calls: an agonistic grunt and a boatwhistle associated with courtship (Fish 1954; Tavolga 1958,1960; Gray and Winn 1961). The boatwhistle is produced only by males on nests (Gray and Winn 1961) and is endogenously driven as well as influenced by calling of surrounding males (Winn 1964, 1967, 1972; Fish 1972). A toadfish, not hearing other males, may still boatwhistle for long periods and attract a female. Although toadfish may be influenced to call by the calling of adjacent males, one would assume the circadian patterning of the boatwhistle to be influenced by …


Upland Nesting Of American Bitterns, Marsh Hawks, And Short-Eared Owls, Harold F. Duebbert, John T. Lokemoen Jan 1977

Upland Nesting Of American Bitterns, Marsh Hawks, And Short-Eared Owls, Harold F. Duebbert, John T. Lokemoen

United States Fish and Wildlife Service: Publications

Nests of American Bitterns (Botaurus lentiginosus), marsh hawks (Circus cyaneus), and short-eared owls (Asio flammeus) are usually found in wetland habitats. Although large marshes containing dense stands of bulrushes (Scirpus), cattails (Typha), or other wetland vegetation are favored nesting cover, these birds have also been reported to nest in stands of tall, dense shrubs and grasses on the upland (Bent 1961, 1963; Palmer 1962; Sealy 1967; Stewart 1975). During 1968-74, we regularly found upland nests of these three species while conducting duck nesting studies in planted fields of undisturbed grass-legume …


Fisheries Report No 28 - The Western Rock Lobster Fishery 1974-1975, G. R. Morgan, E H. Barker Jan 1977

Fisheries Report No 28 - The Western Rock Lobster Fishery 1974-1975, G. R. Morgan, E H. Barker

Fisheries Research Reports

The fishery for the western rock lobster Panultrus eygnus is one of the most important single fisheries in Australia and an important export earner for the State. The fishery is governed by a complex set of regulations which have been reviewed by Bowen (1971) and which are designed to limit the total effort to acceptable levels and to enforce a legal minimum size. It is thus important to constantly monitor the state of the fishery both to ensure that the effort is remaining within the accepted limits and that the regulations are adequately performing their function of maintaining reasonably stable …


A Comparison Of The Leaf Anatomy And Leaf Water Potentials Of Six Populations Of Quercus Occurring At Four Elevations In The San Bernardino Mountains Of Southern California, Roger Kahns Jan 1977

A Comparison Of The Leaf Anatomy And Leaf Water Potentials Of Six Populations Of Quercus Occurring At Four Elevations In The San Bernardino Mountains Of Southern California, Roger Kahns

Theses Digitization Project

No abstract provided.


Serradella : A Pasture Legume For Sandy Soils, John Sylvester Gladstones, N. R. Mckeown Jan 1977

Serradella : A Pasture Legume For Sandy Soils, John Sylvester Gladstones, N. R. Mckeown

Journal of the Department of Agriculture, Western Australia, Series 4

French serradella grows well on many of the sandy soils along the west coast where other species such as sub clover often fail, and produces excellent feed both when green and in the dry state.

Establishment is easy because of its soft seedednedd. However the same characteristic, together with its erect growth habit, means that persistence under grazing has been poor.

This paper looks at work being done to understand the requirements to maximise results from serradella and develop better varieties.


Polythene Storage Improves Lupin Seed Germination, G H. Walton Jan 1977

Polythene Storage Improves Lupin Seed Germination, G H. Walton

Journal of the Department of Agriculture, Western Australia, Series 4

Seed storage trials indicate a practical means of maintaining sandplain lupin seed at a moisture content that limits hard seed development, leading to a commercially acceptable germination rate in the following season.


Revision Of Pectis Section Pectidium (Compositae: Tageteae), David J. Keil Jan 1977

Revision Of Pectis Section Pectidium (Compositae: Tageteae), David J. Keil

Biological Sciences

Pectis L. sect. Pectidium (Less.) A. Gray is a small but very wide-ranging group of taxa. The geographic range of this section includes both insular distribution patterns and broad disjunctions. In an effort to clarify the systematic relationships and to provide a possible explanation for the interesting distribution patterns, I undertook an investigation of this section.


Clematis Coahuilensis (Ranunculaceae), A New Species From North-Central Mexico, David J. Keil Jan 1977

Clematis Coahuilensis (Ranunculaceae), A New Species From North-Central Mexico, David J. Keil

Biological Sciences

Floristic investigations in the Cuatro Cienegas basin and nearby mountain ranges in Coahuila, Mexico, have resulted in the discovery of a previously undescribed species of Clematis (Ranunculaceae). The new species, Clematis coahuilensis, is apparently restricted to the Chihuahuan Desert Region and adjacent segments of the Sierra Madre Oriental. Its known distribution is centered in Coahuila.


Chromosome Studies In North And Central American Species Of Pectis L. (Compositae: Tagetaea), David J. Keil Jan 1977

Chromosome Studies In North And Central American Species Of Pectis L. (Compositae: Tagetaea), David J. Keil

Biological Sciences

Chromosomal modification is often a major factor in the evolutionary diversification of a large, rapidly evolving genus. Pectis, the largest and most widespread genus in the New World tribe Tageteae (Compositae), has radiated into a variety of habitats during its evolutionary history. Until relatively recently, however, little has been known of the role of chromosomal change in the evolution of the genus. Pectis was cytologically unknown until the studies of Raven and Kyhos (1961) and of Turner, Ellison, and King (1961). Subsequently, additional counts have been reported for several taxa (Table 1). To date, however, only a few of …


Movement Of Soil Nitrate Through A Pembroke Soil As Affected By Tillage Method And Time Of Nitrogen Application, Noel T. Johnston Jan 1977

Movement Of Soil Nitrate Through A Pembroke Soil As Affected By Tillage Method And Time Of Nitrogen Application, Noel T. Johnston

Masters Theses & Specialist Projects

Of all the plant nutrients, nitrogen has been subjected to the most extensive study. The amount of inorganic nitrogen in the soil is small while the quantity needed annually by crops is comparatively large. Of the macronutrients usually applied in commercial fertilizers, nitrogen seems to have the quickest and most pronounced effect on plant growth.

In applying the nitrogen fertilizer for crop use, one must be concerned with placement, form, and availability, and with keeping the fertilizer where it is placed throughout the critical part of the growing season. The nitrogen supply molded by non-leguminous plants is of extreme importance …