993 resultados para Texas


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The spillway of Lake Waxahachie, Ellis County (Texas), exposes a > 17 m section of the Hutchins Member of the Austin Chalk Group, un-conformably overlain by Taylor Clay. The Austin sequence was regarded as a potential Global Stratotype Section for the base of the Campanian Stage at the 1995 Brussels meeting on Cretaceous Stage boundaries, with the last occurrence of the crinoid Marsupites testudinarius (von Schlotheim, 1820) as the potential boundary marker. An integrated study of the geochemistry, stable carbon and oxgen isotopes, nannofossils, planktonic foraminifera, inoceramid bivalves, ammonites and crinoids of this section place the last occurrence of M. testudinarius in a matrix of eighteen ancillary biostratigraphic markers, while the boundary can also be recognised on the basis of a delta C-13 excursion that can, in principle, be detected globally in marine sediments. A new forma of the crinoid Marsupites testudinarius is introduced. The Waxahachie section fulfils sufficient geological criteria as to be an excellent candidate GSSP for the base of the Campanian Stage, if problems of ownership and access to the section can be resolved.

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Female crickets respond selectively to variations in species-specific male calling songs. This selectivity has been shown to be age-dependent; older females are less choosy. However, female quality should also affect female selectivity. The effect of female quality on mate choice was examined in Gryllus integer by comparing the phonotactic responses of females on different diets and with different parasite loads to various synthetic models of conspecific calling song. Test females were virgin, 11-14 days old, and had been maintained on one of five diets varying in protein and fat content. Phonotaxis was quantified using a non-compensating Kugel treadmill which generates vector scores incorporating the speed and direction of movement of each female. Test females were presented with four calling song models which differed in pulse rate, but were still within the natural range of the species for the experimental temperature. After testing, females were dissected and the number of gregarine parasites within the digestive tract counted. There were no significant effects of either diet or parasitism on female motivation to mate although the combined effects of these variables seem to have an effect with no apparent trend. Control females did not discriminate among song types, but there was a trend of female preferences for lower pulse rates which are closest to the mean pulse rate for the species. Heavily parasitized females did not discriminate among pulse rates altho~gh there was a similar trend of high vector scores for low pulse rates. Diet, however, affected selectivity with poorly-fed females showing significantly high vector scores for pulse rates near the species mean. Such findings raise interesting questions about energy allocation and costs and risks of phonotaxis and mate choice in acoustic Orthoptera. These results are discussed in terms of sexual selection and female mate choice.

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In the past ten years, many researchers have focussed their attention on parasites regarding the role they may play in causing variations in male secondary sexual traits and subsequent effects on female choice. Male age has also been suggested to be an important factor in female choice if old age reflects superior genes. This study investigated the effects that gregarine gut parasites, age, and diet have on the calling and mating behaviour of the male Texas field cricket, Gryllus integer. Male calling songs were recorded in the laboratory using a Digital Signal Processing Network. The song parameters measured were: pulse rate, pulse width, burst duration, pulses per burst, interburst interval, and percent missing pulses. The effects of parasite load and age on the various calling song parameters was investigated in crickets that were fed two different diets varying in nutritional quality. None of the calling song parameters were affected by either parasite load or age in either diet grou p. Courtship behaviour was ob served and recorded using an Eventlog recorder on an IBM computer in the laboratory. Females mated equally with paras(tized and unparasitized males and with old and young males The total duration and proportion of time spent performing each of 9 courtship displays were recorded for males on each diet. Only one display was affected by parasite load. Highly parasitized males fed the nutritionally inferior diet juddered for a proportionately shorter time than males with low parasite loads. Also, older males performed juddering and shaking antennae proportionally longer and juddering and raising wings for longer durations than younger males. Males that successfully mated were observed for performance of 8 post-copulatory guarding behaviour displays. None of the guarding behaviours were affected by parasite load. However, one display was affected by age, with older males performing guard turning for shorter durations than younger males. Results are discuss,ed in terms of the influence of parasites and age on female choice.

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Studio portrait of Paul Williams, nephew of C. C. Chapman, Fort Worth, Texas. He worked in Chapman's Fullerton office, 5th floor, N. Spadra Street [now Harbor Blvd.], Fullerton, California.

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Printed blank of Statement of Security Form naming the bond as Jones County Texas Bonds for the purpose of building a courthouse. It is made out to S.D. Woodruff and dated June 12, 1885. An envelope addressed to Mr. S.D. Woodruff is also included. The postmarks are Kansas, 1885 and St. Catharines, June 13, 1885.

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Iron Mountain Route Railway schedule: the great through line St. Louis, Arkansas and Texas to the Hot Springs of Arkansas.

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Letter to H.H. Collier of Austin, Texas to the care of Cruger and Moore of Houston, Texas and New Orleans. The letter is from his sister, E. Richards. She writes about family life, her job as a teacher and politics (3 ¼ pages, handwritten), Jan. 23, 1841.

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Letter to H.H. Collier of the Auditor’s Office in Austin, Texas from D.W. Fitch (3 pages, handwritten), publisher of the Houston Star Newspaper. The letter is about newspaper business and personal matters. It is stated that Henry might go to Austin. This letter has been torn and taped. This does not affect the text, Feb. 28, 1841.

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Letter to H.H. Collier of Houston, Texas from J. M. Long and delivered by Captain Daniels. This is a friendly letter in which he mentions that General Edward Burleson has gone on an Indian campaign. Also mentioned are the Indian raid in Austin, the stealing of horses and candidates for the election. He also talks about a ball in Austin. This is actually quite a poetic letter in his description of how Austin used to be and what Austin has become (3 pages, handwritten), Aug. 26, 1842.

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Letter to H.H. Collier of Washington, Texas from Major Nicholas Cruger (3 pages, handwritten) regarding copies of laws that he has sent to Mr. Collier. He asks him to call on Mr. Farland and request him to have a subpoena issued in the case of Garrison vs. John Manson. This letter is torn and taped. This does not affect the text, Mar. 6, 1844.

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Letter to H.H. Collier of Houston, Texas from his friend Elisa. She expresses her desire to go to Galveston but she cannot make it in the fall. This letter is torn and taped but this does not affect the text (2 pages, handwritten), Oct. 13, 1844.

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Letter to H.H. Collier of the Houston, Texas Telegraph Office from Jim Long of Austin, Texas. Mr. Long writes about the horrible shooting of Mr. James Smith by his overseer, Mr. R. Baker. This letter is torn and taped. A small portion of the bottom of the letter is torn away. This slightly affects the text (2 pages, handwritten), Jan. 25, 1845.

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Letter addressed to Jeremiah Jackson of Wall Street, New York from his brother A. Jackson, Austin, Texas. This letter introduces his brother A, Jackson to Mr. Collier. Mr. Collier delivered the letter on his way home to St. Catharines, April 14, 1845.