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Captive breeding of non-domestic birds has increased dramatically in this century, and production of young often exceeds that of the same number of birds in their native habitat. However, when infertility is a problem, artificial insemination can be a useful method to improve production. Artificial insemination programs with non-domestic birds...

1. Although bird censuses are imprecise, they have considerable value in a relative sense. 2. If the techniques are designed so as to minimize effects of variables that can be controlled, valid comparisons may be made among bird populations of two or more plots. 3. The spot-mapping method...

No abstract available....

Tungsten is determined in 11 USGS standard rocks by a spectrophotometric procedure that measures the absorbance of the tungsten-dithiol complex. The results are compared with those obtained by other methods. After the samples are dissolved in HClO4 and HF, the tungsten-dithiol complex is extracted into isoamyl acetate and then back-extracted...

In The Geysers-Clear Lake area of northern California, a fragmented Upper Jurassic ophiolite overlain depositionally by the Great Valley sequence is juxtaposed over deformed and metomorphosed rocks of the Franciscan assemblage along the Coast Range thrust. The basal strata of the Great Valley sequence consist of thick breccias of mafic...

Ninety-seven hot-spring and geyser samples (field acidified to pH<1.4 with HCl or HNO3) from Yellowstone National Park, Wyo., were analyzed for PO4-P using reduced molybdenum-blue and the selective arsenate reducing agent, metabisulfite-thiosulfate. The PO4-P concentrations ranged from below detection limit (~1-73 micrograms per liter). Twenty-five springs had PO4-P concentrations exceeding 6.8 μg/L;...

Tertiary-treated sewage effluent was injected into the Magothy aquifer at Bay Park, Long Island, N.Y., between 1968 and 1973. In 1977, the microbial flora in water samples from the injection well and from three nearby wells were surveyed. Differences in the composition of the microbial flora among the four wells...

R. A. Vollenweider's (1975) nonconservative model described concentrations of nitrogen and phosphorus for 1969-70 in Lake Okeechobee, Fla., better than the models of F. Biffi in 1963, R. H. Rainey in 1967, and R. Piontelli and V. Tonolli in 1964. Vollenweider's model predicted concentrations of 1.4 milligrams per liter of...

The rugose coral genus lowaphyllum is uncommon but widely distributed in rocks of Devonian age. It is here reported for the first time from western North America (Late Devonian). lowaphyllum is also known from the late Middle and Late Devonian of Eastern North America, but the lack of Early and...

Fluid inclusions in ore zones of porphyry systems indicate that extensive boiling of hydrothermal fluids accompanies deposition of ore and gangue minerals. The boiling commonly accompanied a change from a lithostatic to a hydrostatic environment during evolution of an epizonal stock. Pressure gradients near the margin of the stock can...

Leaching of black bedded chert from the Ford Lake Shale, Kandik Basin, Alaska, with dilute hydrofluoric acid resulted in the complete separation of moderately well preserved radiolarians. Preliminary study of an assemblage obtained from the lower half of the formation revealed six to eight forms apparently identical to specimens previously...

The original interpretation of Olivellites plummeri Fenton and Fenton as the trace of an infaunal gastropod, is reconsidered and rejected. The original slab bearing several examples of O. plummeri has been reexamined and reillustrated. The slab came from the type-locality of O. plummeri in Eastland County, Tex., and is a shallow...

Landsat multispectral scanner digital data from four bands were analyzed using computers to produce land use and land cover information of the Puget Sound region, Wash., for use by agencies in that area. The data were first geographically registered to map coordinates. This registration enabled samples of known land cover...

Detrital iron-titanium (Fe-Ti) oxide minerals of the ulvospinel-magnetite (titanomagnetite) and ilmenite-hematite (titanohematite) solid solution series are common in uranium-bearing sandstones. Alteration of Fe-Ti oxide minerals in oxidizing environments formed secondary products (primarily hematite) that are distinct from those produced under reducing conditions (iron disulfide minerals). Oxidation of sulfidized Fe-Ti oxide...

In convection systems with boiling springs, geysers, fumaroles, and other thermal features, the modes of heat flow become increasingly complex as a single liquid phase at depth rises into the near-surface environment where heat flows by convection of liquid and vapor and by conduction in high thermal gradients. This paper...

Six pulses of igneous activity ranging in age from Jurassic to Pliocene have been identified in the Edna Mountain quadrangle, Humboldt County, Nev. Porphyritic syenite am! quartz monzonite of Jurassic age (146-164 million years) at Buffalo Mountain are highly potassic through a wide range in SiO2 content from olivine-bearing syenite...

 A modified visual method for determining the solubility of highly soluble salts in aqueous media up to 100° C is presented. The solubilities of NaCl, KCl, CaCl2, Na2SO4, and K2SO4 were determined up to 100° C. The tabulated experimental data and the fitted equations describing the data indicate that the...

No abstract available....

Pollen analysis of a section of lake sediments at Grassy Lake Reservoir indicates a vegetational sequence changing from tundra, to spruce-fir-pine forest, to pine forest, to tundra at the top. Pollen analysis of a section of lake sediments on Beaverdam Creek indicates a tundra vegetation at the base, followed by...

The Ancient Gneiss Complex (AGC) of Swaziland, an Archean gray gneiss complex, lies southeast and south of the Barberton greenstone belt and includes the most structurally complex and highly metamorphosed portions of the eastern Kaapvaal craton. The AGC is not precisely dated but apparently is older than 3.4 Ga. The...

Textural-distribution patterns of sea-floor sediments on the South Texas continental shelf between Matagorda Bay and the U.S.-Mexico international boundary were evaluated as part of a regional environmental-studies program. Sediment textural gradients support a conceptual model for the regional sediment-dispersal system, which is characterized by both net offshore transport and net...

The North American Cordillera near the Fortieth Parallel consists of the following tectonic units: 1. (A) To the east is a reactivated cratonic area, in the Southern Rocky Mountains and Colorado Plateau, in which the supracrustal rocks (Cambrian to Cretaceous) were broadly deformed during the late Cretaceous-Paleocene Laramide orogeny, and...