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Taxonomy And Ecology Of Fresh-Water Ostracods Of South-Central Texas, Charles Davidson Wise

Biology ETDs

The Ostracoda (Gk. ostrakon, a shell, and eidos, form) are extremely interesting crustaceans that differ from most crustaceans in possessing strongly calcified, bivalve carapaces, Ostracods occur in great abundance in all types of waters, both marine and non-marine. With the exception of very transient waters, probably as many as 90% or more of the bodies of fresh water in North America contain ostracods. Because the carapaces are easily fossilized, ostracods are abundant in deposits ranging from the Ordovician to the present.

The Hemodynamic Changes In Anesthetized Dogs Subjected To Hypoxia And Cold, Virden A. Dohner

Biology ETDs

The combined effects of hypoxia and cold no doubt were known by the ancients in the areas of the world where there are mountains of considerable height. But the ancients feared the mountains (6) and therefore have left no precise information which might incline one to believe they noted symptoms of physiological significance.

A Study Of The Mitotic Karyotypes Of Five Species Of Culicine Mosquitoes Found In New Mexico, David A. Laycock

Biology ETDs

Karyotypic studies were made of five species of mosquitoes: Culex tarsalis Coquillett, Culex pipiens quinquefasciatus Say, Culiseta incidens (Thomson), Psorophora signipennis (Coquillett), and Aedes dorsalis (Meigen). Slides of tissue from the limb buds were prepared by the squash technique. All five species were found to have a diploid number of six. The study shows that Aedes dorsalis, Psorophora signipennis, and Culiseta incidens have virtually identical mitotic karyotypes, with two pairs of large and one pair of somewhat smaller chromosomes. Culex tarsalis and Culex pipiens quinguefasciatus have karyotypes that contain three sizes of chromosomes. In Culex tarsalis there are obvious size …

A Comparative Study Of The Antidiuretic Hormone Bio-Assay Using Three Species Of Bufo, Jeanne Marie Jordan

Biology ETDs

This study was designed to (1) determine and compare the sensitivity of three species of Toads of the genus Bufo to the hormone Pitressin, a commercial anti-diuretic hormone, (2) determine and compare the suitability of three species of Bufo as subjects in anti-diuretic hormone bio-assay, and (3) compare the physiological responses of the three species to the injected hormone.

Influence Of Auxins On Growth And Development Of Excised Embryos Of Pinus Ponderosa, Virgil K. Howe

Biology ETDs

The purpose of the experiment was to examine the influences of selected auxins upon seedling development post germinal cultures of excised embryos of Pinus ponderosa Laws (ponderosa pine). Seedlings were studied on an agar medium and later in quartz sand with added nutrients.

Mammals Of Mount Taylor, Valencia County, New Mexico, Eugene E. Schroeder

Biology ETDs

During the summer of 1960, three months were spent in making a comprehensive study of the kinds and ecological distribution of native mammals in and above the Transition Zone on Mount Taylor of Valencia County, New Mexico.

Mount Taylor, and old volcanic pile, rises 11,301 feet above sea level. Three boreal life zones, the Transition, Canadian, and Hudsonian were assigned to Mount Taylor.

Small mammals were collected by two sampling methods, quadrant and line trapping. However, mist nets were used for capturing bats. Quadrants were placed in various plant communities for three successive nights. Numbers and kinds of mammals recorded …

Some Aspects Of The Life History Of The Silky Pocket Mouse In New Mexico, Richard B. Forbes

Biology ETDs

Pocket mice of the subgenus Perognathus, especially those of the little known species Perognathus flavus Baird, present several interesting ecologic and taxonomic problems. A prerequisite of studies of these problems is a knowledge of extent of individual morphological variation attributable to age. A purpose of his paper is to investigate the relationship of age to size, molt and pelage, reproductive activity, and season in the silky pocket mouse. Another purpose is to analyze the summer food habits of P. flavus as revealed by study of several large series of pocket mice collected during August of 1958.

Geographic Variation Of The Hispid Cotton Rat In New Mexico, A.L. Gennaro

Biology ETDs

A total of 520 cotton rats, Sigmodon hispidus, was examined to determine the kind and amount of geographic variation of these animals in New Mexico.

The distributional history of Sigmodon hispidus in New Mexico may be revealed by a relationship between color variation of these animals and soil color of areas from which these animals were taken. This relationship suggests, firstly, that Sigmodon hispidus has occupied the southern Rio Grande Valley for a longer period of time than it has areas east of the Rio Grande Valley, and secondly, that Sigmodon hispidus has only recently occupied the Deming Plain. …