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Full-Text Articles in Life Sciences
Biometrical Study Of Goniobasis Comalensis Pilsbry From Two Diverse Habitats, Elmer P. Cheatum, E. D. Mouzon, Jr.
Biometrical Study Of Goniobasis Comalensis Pilsbry From Two Diverse Habitats, Elmer P. Cheatum, E. D. Mouzon, Jr.
Field and Laboratory
Much has been written on the part played by the environment in changing secondary characters of the more plastic invertebrates….During February, 1934, a collecting trip was made to San Marcos, Texas, where two contrasting aquatic habitats were found, both of which were inhabited by the branchiate snail Goniobasis comalensis. Several hundred individuals were collected from each habitat, the shells measured, and a statistical study made of size differences.
Collecting Fossil Elephants At Dallas, Texas, Ellis W. Shuler
Collecting Fossil Elephants At Dallas, Texas, Ellis W. Shuler
Field and Laboratory
That man was co-existent with the mastodon and mammoth in Europe is well established. Many geologists and archaeologists are convinced that man lived in North America during the Pleistocene but the belief is by no means universal. Certainly the archaeologist has a definite interest in the search for fossil elephants and for any evidence of their association with man….Elephants were widespread and numerous in Texas during the Pleistocene.
The Ruffle Plant Again In Limpia Creek, Mayne Longnecker
The Ruffle Plant Again In Limpia Creek, Mayne Longnecker
Field and Laboratory
For the first time in thirty-two years the ruffle plant, Riella americana, rare American liverwort, has been collected in Limpia Creek, in the Davis Mountains of western Texas.
That First Texas Botanist, S. W. Geiser
That First Texas Botanist, S. W. Geiser
Field and Laboratory
Winkler, in his useful account of botanical investigations in Texas, states (p. 5) that Jean Louis Berlandier, a French botanist in the employ of the Mexican Government, was the first to explore Texas botanically, while connected (1828) with the Comision de Limites under General Mier y Teran. In the present writer's own published studies, this statement was repeated, since the collections of Dr. Edwin James while a member of Long's Rocky Mountain Expedition (1819-20) were made in territory not a part of the historic province of Texas, but of Chihuahua, as maps of the period will show. In the modern …
A Student Experiment In The Measurement Of Vapor Pressure, Fitzhugh Marshall
A Student Experiment In The Measurement Of Vapor Pressure, Fitzhugh Marshall
Field and Laboratory
The purpose of this experiment was to determine the changes in the vapor pressure of benzene with changes in temperature; and from these data to derive a vapor pressure-temperature curve.
The Blanton Student Observatory, John D. Boon
The Blanton Student Observatory, John D. Boon
Field and Laboratory
All of the large observatories, that have been constructed in recent years, are located in high and dry altitudes where the sky is almost always clear and the atmosphere is steady. It is a useless waste of money to locate a large telescope where climatic conditions are unfavorable…. The situation is quite different when it comes to the construction of small student observatories such as are found on the campus of many of the universities. Every city as large as Dallas, no matter what the atmospheric conditions may be, should have one or more small observatories where students may learn …
Further Observations On The Sex-Ratios Of Terrestrial Isopods, S. W. Geiser
Further Observations On The Sex-Ratios Of Terrestrial Isopods, S. W. Geiser
Field and Laboratory
Vandel contends that in terrestrial isopods the females are more numerous than males in collections. He gives tables showing the sex-ratios of collections of ten species…. Although Vandel finds that the sex-ratios of adult collections are one-sided in favor of the female sex, he nevertheless finds that in cultures of the species which he made, the sexes were about equally represented at birth, and in young populations. This accords with the findings of the present writer, who found the sexes approximately equal in very young populations of Armadillidium vulgare and Porcellio laevis.
Molasses-Agar: A Useful Medium For The Cultivation Of The Genus Monilia, Hardy A. Kemp, Sol Haberman
Molasses-Agar: A Useful Medium For The Cultivation Of The Genus Monilia, Hardy A. Kemp, Sol Haberman
Field and Laboratory
Species of the genus Monilia are easily cultivated between the temperatures of 22°C and 38°C on solid media of slightly acid reaction. After cultivating stock strains of Monilia albicans and Monilia psilosis on Sabouraud's medium, honey agar, and molasses agar, it was found that molasses agar afforded the best means for cultivating these Oosporaceae.
Rainfall On The Western Front During The World War, Edwin J. Foscue
Rainfall On The Western Front During The World War, Edwin J. Foscue
Field and Laboratory
Within the last fifty years many attempts have been made to produce rain by artificial means, but all have resulted in failures. The unusually dry summer of 1934 in central United States, from North Dakota to Texas, produced a new group of rainmakers and rain-making experiments. The details of their plans differed somewhat, but all worked on the so-called "concussion theory" that the detonation of high explosives in the upper atmosphere would produce rain. In each case claims were supported by the commonly accepted statement that rain always followed battles, and that the unusually heavy rain in France along the …
Type Collection Of The Writings Of Robert T. Hill, Ellis W. Shuler
Type Collection Of The Writings Of Robert T. Hill, Ellis W. Shuler
Field and Laboratory
Dr. Robert T. Hill has signally honored the Geological Department of Southern Methodist University by donating to its library the type collection of his writings with an index and annotated bibliography. This collection covers the writings of one of America's leading geologists over a period of nearly half a century. Interesting and valuable in every phase of geology, it is the court of final reference for the student of the history of Texas stratigraphy.
The Distribution Of Pectinatella Magnifica Leidy In The United States, S. W. Geiser
The Distribution Of Pectinatella Magnifica Leidy In The United States, S. W. Geiser
Field and Laboratory
In 1851, Leidy described from the Schuylkill River near Philadelphia, the interesting Bryozoan, Pectinatella magnifica. Since then, it has been recorded from a number of other localities in America and Europe. The exact distribution, however (for America, at least) is still only partially known. Brown1 has recently published a careful study of the biology of this species; and the present writer has studied, since 1928, the distribution of this species in Iowa, as well as its periodicity of abundance.
The Magnetic Field Between A Double Coil, Frank C. Mcdonald
The Magnetic Field Between A Double Coil, Frank C. Mcdonald
Field and Laboratory
One method of obtaining a uniform magnetic field is by means of a double coil. This consists of two coaxial coils, such as those used in the Helmholtz galvanometer.
Vitamin B(B,) And G(B2) Content Of Cottonseed Products, May L. Whitsitt
Vitamin B(B,) And G(B2) Content Of Cottonseed Products, May L. Whitsitt
Field and Laboratory
Cotton is a raw material which is more and more closely allying the agricultural and chemical industries. Because of the considerable industrial importance of cotton to the South and because of the recognized nutritional value of cottonseed meal in cattle feeding, a study of cottonseed products has been undertaken in order to learn more of their possibilities as nutrients. Stevens (8) in 1930 reported his finding that cottonseed meal was a rich source of both vitamins B(B), and G(B2). This investigation has for its object a comparative study of cottonseed meal, oil, and hulls with respect to their vitamin B …
An Annotated List Of The Snails Of Dallas County, Texas (Concluded), Elmer P. Cheatum, Charles E. Burt
An Annotated List Of The Snails Of Dallas County, Texas (Concluded), Elmer P. Cheatum, Charles E. Burt
Field and Laboratory
No abstract provided.
The Distribution Of Population In The Lower Rio Grande Valley Of Texas, Edwin J. Foscue
The Distribution Of Population In The Lower Rio Grande Valley Of Texas, Edwin J. Foscue
Field and Laboratory
The Lower Rio Grande Valley of Texas represents one of the most densely populated areas of southwestern United States. Its average density, 40.9 people per square mile, is nearly twice that for the state as a whole. The four counties of the Valley area include large tracts of nearly vacant ranch country. Were figures available for the irrigated area alone, the average density per square mile would be much greater.
Notes On Texas Crustacea, S. W. Geiser
A.A.P.G. Meeting At Dallas, Ellis W. Shuler
A.A.P.G. Meeting At Dallas, Ellis W. Shuler
Field and Laboratory
Geology students of Southern Methodist University found a rare opportunity in attending the annual meeting of the American Association of Petroleum Geologists in Dallas, March 21-24, 1934. This meeting brought together more than 1500 professional geologists, world wide in distribution. The Association is one of the largest and strongest of scientific bodies. Its publications and programs are of outstanding interest in the field of geology. The program for 1934 was one of unusual merit and was distinguished by the number of papers on geological principles and pure science rather than applied geology.