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The Systematic Position Of The Avian Species Metopothrix Aurantiacus, J. Alan Feduccia
The Systematic Position Of The Avian Species Metopothrix Aurantiacus, J. Alan Feduccia
Journal of the Graduate Research Center
The Orange-fronted Softtail, Metopotlzrix aurantiacus, now known to occur in the upper Amazon in southeastern Colombia, eastern Equador, eastern Peru, western Brazil, and northeastern Bolivia (Peters, 1951: 115) was described by Sclater and Salvin (1866: 190-191), who placed it in the Pipridae. Sclater (1888: 292) retained Metopothrix in the Pipridae without comment, placing it between Masius and Pipra. Berlepsch (1903: 108), in reviewing the systemic position of the genus stated that "this bird is not a Piprine [sic] form, as was believed by its describers, but a Dendrocolaptine [sic], closely allied to Xenerpestes, and agreeing with it in general characters …
Adrenal Corticosteroidogenesis And Hypothyroidsm: Effect Of Long-Term Treatment With P-Aminobenzoic Acid, John L. Mccarthy, Linda W. Laury
Adrenal Corticosteroidogenesis And Hypothyroidsm: Effect Of Long-Term Treatment With P-Aminobenzoic Acid, John L. Mccarthy, Linda W. Laury
Journal of the Graduate Research Center
The relationship between induced hypothyroidism and adrenal involution has been studied by a variety of approaches in an attempt to elucidate the physiological basis between the events. McCarthy et al. (1959) reported on an investigation of feeding several antithyroidal agents to rats to study adrenal gland involution. While adrenal involution did occur following treatment with several of the goitrogens, only in one case was there a difference in peripheral plasma adrenal corticoid levels. In rats fed p-aminobenzoic acid (PABA) for 12 weeks, peripheral levels of corticosterone (B) decreased and levels of a Porter-Silber positive chromogen increased markedly. Work from the …
Preface, Joe P. Harris
Preface, Joe P. Harris
Journal of the Graduate Research Center
When classes started in the Fall, 1969, at Southern Methodist University, it was the first time in forty-two years that Mayne Longnecker was not present to greet the new students on campus.
Natural History Of The Avian Families Dendrocolaptidae (Woodhewers) And Furnariiae (Ovenbirds), J. Alan Feduccia
Natural History Of The Avian Families Dendrocolaptidae (Woodhewers) And Furnariiae (Ovenbirds), J. Alan Feduccia
Journal of the Graduate Research Center
During my investigations of the evolution of the woodhewers and ovenbirds I attempted to gather together data on the natural history of the groups and synthesize it into a meaningful form. In this summary I have stressed habitat, food, foraging behavior, and nidification. Although it should be realized that the present generic limits (Peters, 1951) are at best tentative, I thought it best to summarize the natural history according to the present classification. As most of the future changes in the classification of these groups will very likely involve lumping of genera, the information contained herein should remain separable to …
Fine Structure Of The Fibrillar Flight Muscles In The Housefly, Musca Domestica (Diptera), R. S. Sohal, V. F. Allison
Fine Structure Of The Fibrillar Flight Muscles In The Housefly, Musca Domestica (Diptera), R. S. Sohal, V. F. Allison
Journal of the Graduate Research Center
Insects of the orders Hemiptera, Hymenoptera, Coleoptera and Diptera have developed an asynchronous flight mechanism. The frequency of the muscle contraction is not directly related to the rate of nervous stimulation (Pringle 1965). An initial nervous stimulus produces an active state in the flight muscle during which a variable number of oscillatory contractions take place. Consequently, insects like the house-fly can maintain a very high frequency of wing beat (180-200 per second). Asynchronous flight muscles differ from the vertebrate skeletal muscles and insect synchronous flight muscles; in the latter each nerve impulse produces a single contraction of the innervated fibres. …
A New Shorebird From The Upper Pliocene, J. Alan Feduccia
A New Shorebird From The Upper Pliocene, J. Alan Feduccia
Journal of the Graduate Research Center
One of the avian fossils recovered from the Saw Rock Canyon local fauna of the Upper Pliocene of Seward County, Kansas, is the humerus of a scolopacine shorebird which closely resembles the Recent Tringa solitaria. Present evidence favors a late Hemphillian age for the fauna (Hibbard, 1964. Pap. Michigan Acad. Sci., Arts, and Letters, 49: 115-127), and the fauna is taken from a lower section of the Rexroad formation than are the Fox Canyon and Rexroad local faunas of the Rexroad formation of Meade County, Kansas. Many of the mammals in the Saw Rock Canyon local fauna are considered to …
Fine Structure Of Nucleoli In Cells Of Encysted Hymenolepis Diminuta, John E. Ubelaker
Fine Structure Of Nucleoli In Cells Of Encysted Hymenolepis Diminuta, John E. Ubelaker
Journal of the Graduate Research Center
Studies of the fine structure of 5 day old cysticercoids of H. diminuta revealed nucleoli with well-formed lamellae in germinal cells within the body of the encysted worm. The nucleoli were located centrally in the nucleus and appeared not to be attached to the chromosomes, chromatin, or to the nuclear envelope.
Evidences Of Diurnal Feeding Activity In Trichoptera Larvae, John O. Mecom
Evidences Of Diurnal Feeding Activity In Trichoptera Larvae, John O. Mecom
Journal of the Graduate Research Center
The literature of the aquatic insect order Trichoptera (caddisflies) is extensive. Ross (1944), Denning (1950a, 1950b, 1954, 1956), Banks (1944) and Betten (1934), among others, have been major contributors to the taxonomy and zoogeography of North American species. Important studies of the general ecology of both adult and larval forms have been made by Lloyd (1921), Scott (1958), and Hynes (1961) but Mecom and Cummins (1964) have commented on the limited knowledge of the trophic relationships of Trichoptera. Hanna (1957), Jones (1950), Chapman and Demory (1963) studied the food ingested by Trichoptera larvae, but except for the very limited experiments …
Dialysis Studies Of The K+ Binding Capacity Of Physarum Polycephalum, Claude Nations
Dialysis Studies Of The K+ Binding Capacity Of Physarum Polycephalum, Claude Nations
Journal of the Graduate Research Center
Anderson (1964) has observed that migrating plasmodia of the slime mold, Physarum polycephalum, maintain a higher concentration of K+ in the region of the advancing front than in the posterior trailing region. He has also found that most of the Na- but little of the K+ in the posterior region can be removed by flushing water over the organism. Previous work by Anderson (1962) had revealed that alcohol precipitates prepared from plasmodial homogenates contain considerable quantities of K- which cannot be removed by washing. Based on these discoveries he has suggested that K+, but not Na+ is closely associated with …
Morphological Variation In Cephalogonimus Americanus (Trematoda: Cephalogonimidae) From Amphibians In Colorado, John E. Ubelaker, John D. Kimbrough
Morphological Variation In Cephalogonimus Americanus (Trematoda: Cephalogonimidae) From Amphibians In Colorado, John E. Ubelaker, John D. Kimbrough
Journal of the Graduate Research Center
A collection of western toads, Bufo boreas Baird and Girard, 1852, and neotenic tiger salamanders, Ambystoma tigrinum (Green) from Sheep Lake, Horseshoe Park, Rocky Mountain National Park, Colorado, were examined for helminths in the spring of 1966. Oswaldo-Cruzia subauricularis (Rudolphi, 1819) was found in Bufo boreas and Ophiotaenia filarioides (LaRue, 1909) in Ambystoma tigrinum. In addition, both hosts harbored Spironoura pretiosa Ingles, 1936, Phylloclistomum bufonis Frandsen, 1957 and Cephalogonimus americanus. The last species differed greatly in appearance in the two hosts and these differences are reported herein.
Bidding For Offshore Oil: Toward An Optimal Strategy, Keith C. Brown
Bidding For Offshore Oil: Toward An Optimal Strategy, Keith C. Brown
Journal of the Graduate Research Center
The outcome of the drilling of a wildcat well on a lease is almost never known precisely at the time the well is drilled. In fact, even a probability density function of the present values of the possible outcomes is typically not known with certainty. But even wildcat wells are not drilled blindly; before a rational entrepreneur undertakes such a project, he must have enough information to convince him that the possibilities of gain are sufficient to justify the drilling costs. Thus, it can be persuasively argued that, although a potential investor may not be able to specify an objective …
Comparative Osteology Of The Pelvic Girdles Of The Phyllostomatidae (Chiroptera; Mammalia), Dan W. Walton, Gloria M. Walton
Comparative Osteology Of The Pelvic Girdles Of The Phyllostomatidae (Chiroptera; Mammalia), Dan W. Walton, Gloria M. Walton
Journal of the Graduate Research Center
The Chilonycterinae are the most primitive of the subfamilies of the Phyllostomatidae. Two basic groups comprise this subfamily: the first includes the genera Pteronotus and Chilonycteris; the second, the genus Mormoops. This grouping is based principally upon the characteristics of the humerus and the innominate. Within the subfamily Phyllostomatinae two types are recognized. The Macrotus-type is considered the more primitive, because of its resemblance to the chilonycterines, and the Phyllustomus-type the more advanced. From these two phyllostomatine groups are derived the more advanced lines of the Phyllostomatidae. The phyllonycterine line appears to be derived from the Macrotus-type. The sturnirine-glossophagine line …
Hashin Bounds For Aggregates Of Cubic Crystals, Gene Simmons
Hashin Bounds For Aggregates Of Cubic Crystals, Gene Simmons
Journal of the Graduate Research Center
Bounds for the elastic properties of aggregates of cubic crystals are calculated from the single crystal data according to the scheme developed by Hashin and Shtrikman. These bounds are better by an order of magnitude for most materials than those provided by the Voigt and Reuss averages. Values of rigidity, Young's modulus, Poisson's ratio, and velocity of both compressional and shear waves are tabulated for about 900 cubic specimens.
Missourian Facies In The Possum Kingdom Vicinity, Palo Pinto County, Texas, E. G. Wermund
Missourian Facies In The Possum Kingdom Vicinity, Palo Pinto County, Texas, E. G. Wermund
Journal of the Graduate Research Center
The uppermost Keechie Creek, the Palo Pinto, the Wolf Mountain, and the Winchell Formations of the Missourian Series were mapped in the Possum Kingdom vicinity, Palo Pinto County, Texas. The Keechie Creek and Wolf Mountain Formations are dominantly terrigenous facies. The Palo Pinto Formation is an off-bank facies which crops out immediately updip of an equivalent subsurface limestone bank. Both the bank and off-bank facies of the Winchell Limestone crop out in the study area. Typical Missourian terrigenous facies includes mostly unfossiliferous silty clay shales intercalated with a small volume of fine-grained sandstones. Away from equivalent limestone banks the shales …
A Preliminary Report On The Pennsylvanian Canyon Carbonates In North Central Texas, James E. Brooks, Peter Bretsky Jr.
A Preliminary Report On The Pennsylvanian Canyon Carbonates In North Central Texas, James E. Brooks, Peter Bretsky Jr.
Journal of the Graduate Research Center
The Canyon Group comprises an alternating sequence of limestone and shale formations, with sandstone members being common in the shales. The entire succession is crudely cyclic. Within the thickest limestone formation, the Winchell, detailed petrographic studies have shown the existence of regular vertical changes in texture. Three textural units occur, each commencing with arenitic textures at the base and grading upward to lutitic textures in the upper portion. These have been traced over several units and are believed to be referrable to regular changes in the depositional interface of the Winchell Bank with respect to energy base.
Foreword, James E. Brooks
Foreword, James E. Brooks
Journal of the Graduate Research Center
Study of the Pennsylvanian strata in north central Texas has spanned more than half a century and has progressed from general surveys to more detailed studies. The early investigations of the U. S. Geological Survey and the Bureau of Economic Geology of the University of Texas have been supplemented by more recent studies which have been supported by various oil companies. Currently members of the geological faculties at Baylor, Southern Methodist and Texas Christian Universities together with several of their graduate students have undertaken more detailed studies of the Cisco, Canyon and Strawn Groups, respectively. The present volume is intended …
Pennsylvania Canyon Stratigraphy Of North Central Texas, Dan E. Feray, James E. Brooks
Pennsylvania Canyon Stratigraphy Of North Central Texas, Dan E. Feray, James E. Brooks
Journal of the Graduate Research Center
The Pennsylvanian strata of North Central Texas are divisible into three main lithostratigraphic units-in ascending order the Strawn, Canyon and Cisco Groups. The Strawn and Cisco are dominated by sandstones and shales, whereas the Canyon comprises alternating limestones and shales with subordinate sandstones. The subdivision of these units into component formations and members is complicated by the broadly lenticular nature of most of the sandstone and limestone bodies. Thus, for instance, shale formations which at one locality may be separated by a limestone formation may, at another locality, where the limestone has changed facies into shale, be in immediate juxtaposition …
Stratigraphy And Carbonate Petrology Of The Pennsylvanian Upper Canyon Group In Stephens And Palo Pinto Counties, Texas, Peter Bretsky Jr.
Stratigraphy And Carbonate Petrology Of The Pennsylvanian Upper Canyon Group In Stephens And Palo Pinto Counties, Texas, Peter Bretsky Jr.
Journal of the Graduate Research Center
The strata of Pennsylvanian age in north-central Texas dip gently and uniformly to the northwest. They are subdivided, in ascending order, into the Strawn, Canyon and Cisco Groups. The study area was limited to the upper part of the Canyon Group in Stephens and Palo Pinto counties. Four formations were mapped and the petrology described; they are, in ascending order, the Placid Shale, Ranger Limestone, Colony Creek Shale and Home Creek Limestone; also mapped were outliers of the Trinity Group (Cretaceous). All the formations show lateral and vertical lithologic changes; therefore detailed field tracing was necessary to insure accurate stratigraphic …
Echota Funeral Notices, Jack Frederick Kilpatrick
Echota Funeral Notices, Jack Frederick Kilpatrick
Journal of the Graduate Research Center
Chafe and Kilpatrick (1962, p. 61) state that "... it is not so well realized that Oklahoma [Cherokee] speech is far from homogeneous," and express the hope that "... a dialect survey of the area will be carried out while the language still enjoys a vitality approximating that which it has today." The purpose of this paper is to call attention to certain mortuary customs of a small group of Cherokees in west-central Adair County which speaks a distinctive dialect of the Cherokee language.
Significance Of Sharp Structural Boundaries, John W. Harrington
Significance Of Sharp Structural Boundaries, John W. Harrington
Journal of the Graduate Research Center
This paper raises the question of whether sharp structural boundaries define the existence of equally sharply limited tectonic force fields. If so, a new parameter and boundary condition is added in the search for quantitative means to study the deformation of the earth. The illustration of a sharply defined force field of lateral tension is taken from the eastern limit of the Basin and Range Province at Guadalupe Peak, Texas. Lateral compression is shown to have sharply defined qualities along the west side of the Valley and Ridge Province of the Appalachians and the Front Range of Colorado. Contrast is …
Notes On The Alluvial History Of The Lampasas River, Texas, E. P. Cheatum, Bob H. Slaughter
Notes On The Alluvial History Of The Lampasas River, Texas, E. P. Cheatum, Bob H. Slaughter
Journal of the Graduate Research Center
Excavations made in connection with the Stillhouse Hollow Dam construction in Bell County, Texas, offered an excellent view of almost complete sections of the floodplain and the two terraces developed in the valley at this point. In the process of work sponsored by the National Park Service, these sections were measured and their lithology recorded. A molluscan fauna was recovered from approximately two tons of sediments quarried from a shallow zone near the base of the T-1 terrace. A radio-carbon date from shells higher in the same terrace indicates an age of 4970 ± 250 B.P., according to the determination …
Third Bibliography And Index For The Philosophy Of Geology, Claude C. Albritton Jr.
Third Bibliography And Index For The Philosophy Of Geology, Claude C. Albritton Jr.
Journal of the Graduate Research Center
The following bibliography and index have the same scope and structure as the two preceding issues. The categories of writings here cited are also the same as listed in the front portion of the second bibliography.
The Texas Expenditure System: An Evaluation Of Its Growth And Needs, Walton Terry Wilford
The Texas Expenditure System: An Evaluation Of Its Growth And Needs, Walton Terry Wilford
Journal of the Graduate Research Center
Among the more perplexing problems facing state governments since World War II has been the need for substantial increments in the supply of state-supported social goods and services. The demand for these goods has risen considerably more rapidly than demand in the private sector, leading to enormous pressures on most state revenue structures. The State of Texas is no exception. Since 1947 structural problems have emerged within the administrative machinery of disbursing funds, new and expanded programs have been assumed at the state level, and Texas has been required to make important adjustments in its revenue structure. In 1961, faced …
Sequent Occupance In The Santa Clara Valley, California, C. Langdon White
Sequent Occupance In The Santa Clara Valley, California, C. Langdon White
Journal of the Graduate Research Center
The Santa Clara Valley beautifully exemplifies sequent occupance. Here an amazing drama has unfolded from the time of the primitive Amerindian, then through the Spanish and Mexican Period, the days of the cattle barons, the wheat bonanzas, the specialized agriculture at the turn of the century, and finally the period of immigration, urbanization, and industrialization (primarily electronic-missile defense). In his study published in 1932, Jan O. M. Broek dealt with the valley from the time of the Amerindian to the highly specialized horticulture of the 1920s. The present study purposes to telescope the work of Broek and to show that …
The Texas Economy, Stanley A. Arbingast
The Texas Economy, Stanley A. Arbingast
Journal of the Graduate Research Center
For the past six decades, Texas has been in a process of explosive growth. Since 1900 population has more than tripled, from slightly over 3,000,000 to 10,300,000. The key factors in this growth have been the wide diversity of raw materials available for industry and man's recognition of their value as resources. But in 1965, because many of the nation's dynamic new industries are not oriented to raw materials, the people of Texas need to take a new and searching look at those resources which have been the major basis for economic development, for there is already evidence that as …
Perspective On Land Use—American Samoa, Bryan Farrell
Perspective On Land Use—American Samoa, Bryan Farrell
Journal of the Graduate Research Center
American Samoa, a dependent possession of the United States, consists of four small, volcanic islands in the tropical Southwest Pacific. The territory is a physical, ethnic and cultural outlier and close neighbor of the very much larger, independent, Western Samoa. American Samoa has a limited, largely subsistence agriculture, a low level of technology and a population which, since 1956, despite a rapid birth rate, has decreased because of emigration. Western Samoa on the other hand has a well-developed commercial agriculture, a rapidly increasing population and a relatively high economic potential.
Edwin Jay Foscue, Virginia Bradley
Edwin Jay Foscue, Virginia Bradley
Journal of the Graduate Research Center
On the occasion of Dr. Foscue's retirement it has seemed particularly appropriate to honor his forty-two years of teaching at Southern Methodist University with a special issue of the Journal of the Graduate Research Center because in 1932 he became the first editor of Field and Laboratory, the predecessor of the Journal, and in 1960 his paper, "East Texas: A Timbered Empire," comprised the first issue of the renamed and expanded Journal.
Manufacturing In Texas: Facts And Fancy, Tom L. Mcknight
Manufacturing In Texas: Facts And Fancy, Tom L. Mcknight
Journal of the Graduate Research Center
Regional generalizations are common with respect to various parts of the United States, but it is about Texas that they are perpetuated in greatest profusion. In that state, it has been irreverently remarked, one can "look farther and see less" than anywhere else in the nation. This delightful generalization is but one of myriad that have been composed about our erstwhile-largest state. Indeed, the folklore and autochthonous mythology of this country would be much the sparser were it not for the congeries of cliches concocted concerning Texas.
Single Crystal Elastic Constants And Calculated Aggregate Properties, Gene Simmons
Single Crystal Elastic Constants And Calculated Aggregate Properties, Gene Simmons
Journal of the Graduate Research Center
Data on the elastic properties of single crystals have been collected from the literature published through mid-1964. The elastic properties of isotropic aggregates (Young's modulus, Poisson's ratio, shear modulus, bulk modulus, compressibility, velocity of shear waves, and the velocity of compressional waves) are calculated according to the schemes of Voigt and Reuss. The tables include about 1100 determinations.
Second Bibliography And Index For The Philosophy Of Geology, Claude C. Albritton Jr.
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 …