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Water-supply problems in southwest Florida are largely related to the quality, or deterioration in the quality of the water, rather than to the quantity of water available. When we consider that the abundant supply of water visible at the surface is only a fraction of the quantity stored in the...

A seismic-reflection survey was carried out near Denver, Colorado, for the U. S. Geological Survey, to determine if structures exist in the 12,000-ft sedimentary section or in the Precambrian basement that might explain the recent earthquake activity. No major faults were revealed in the sedimentary section. Reflections from a steeply dipping horizon believed to be in the basement complex may be indicative of faulting; however, the magnitude cannot...

The length, age and sex compositions of dead and dying alewives collected in June 1967 at six locations in southern, central, and northern Lake Michigan are compared with those of fish taken in experimental trawls at five locations in April and June 1967. Behavior at the time of death, condition...

Fillmore County, an area 24 miles square, lies in the eastern part of the Nebraska loess plain. Although tributaries of the Big Blue River have eroded valleys into this plain, much of the original surface is intact. Broad flats and numerous shallow undrained depressions characterize the plain. The county is...

No abstract available....

Geologic evidence suggests that a series of ultramafic complexes of the ‘Duke Island type’ located along a 560 km-long belt in southeastern Alaska crystallized from magmas of ultramafic composition. Some geologists have proposed that these magmas were derived by fractional fusion of...

No abstract available....

Reward bands placed on the other leg of certain regularly banded immature mourning doves (Zenaidura macroura) were used to develop information on reporting rates of recovered dove bands. Reports from 15 widely separated sections of the United States showed considerable variation in recovery rate of doves both with and without...

The four species of lampreys native to the upper Great Lakes (American brook lamprey, Lampetra lamotteni; chestnut lamprey, Ichthyomyzon castaneus; northern brook lamprey, I. fossor; and silver lamprey, I. unicuspis) were collected in various stages of their life cycle and maintained in the laboratory until sexually mature. Secondary sex characters...

Returns from mature lake trout (Salvelinus namaycush) tagged in western Lake Superior in 1959 and 1962-65 described here suggest that trout disperse widely from the spawning grounds after spawning and return in subsequent years. Although the data were not extensive, returns from lake trout tagged near Keweenaw Point in 1950...

Hermaphroditism has been reported frequently among many of the Clupeidae, but only one account of hermaphroditism has been published for the alewife, Alosa pseudoharengus. Rothschild discovered four hermaphroditic alewives among 444 fish he examined from Cayuga Lake, New York. We recently collected two hermaphroditic alewives from Lake Michigan....

Infectious pancreatic necrosis (IPN) is a virulent disease of young trouts and is easily transmitted from infected animals through water and with eggs. At present, the most effective control measure consists of propagation of specific pathogen-free stock. Methods are described for using fish cell cultures to detect IPN virus in...

The distribution and environmental disequilibrium patterns of naturally occurring uranium isotopes (U234 and U238) in waters of the Floridan aquifer suggest that variations in the ratios of isotopic activity and concentrations can be used quantitatively to evaluate mixing proportions of waters from differing sources. Uranium is probably unique in its...

The activity product constant of cryolite (Na3AlF6) at 25°C and 1 atm total pressure was calculated from data for solutions from which synthetic cryolite or mixtures of cryolite and a solid apparently related to ralstonite had precipitated. The activities of fluoride and of sodium were estimated using specific ion...

Spheroidal and cupshaped, carbonaceous alga-like bodies, as well as filamentous structures and amorphous carbonaceous matter occur in sedimentary rocks of the Onverwacht Series (Swaziland System) in South Africa. The Onverwacht sediments are older than 3.2 eons, and they are probably the oldest, little-altered sedimentary rocks on Earth. The basal Onverwacht...

Flint pebbles and nodules from the Upper Cretaceous chalks of Europe occur offshore and at many seaports along the Atlantic coast of North America, where they were brought as ship's ballast. Isolated pieces imported from Europe as gunflints also are present....

A cell without liquid junction was used to obtain dissociation constants for the reaction: KSO4− = K+ +SO42−. At 10°, 25°, 38° and 50°C, values for Kdiss KSO4− are, respectively, 0.195, 0.142, 0.117, and 0.095. At 25°C, , and <img class="imgLazyJSB inlineImage" title=""...

Hydration of obsidian has been used to date rhyolite flows, containing obsidian or porphyritic glass, at Glass Mountain (Medicine Lake Highlands) and Mono Lake, California. The method is simple and rapid and can be used to date flows that erupted between 200 and approximately 200,000 years ago....

Water quality of streams tributary to Lakes Superior and Michigan was analyzed for 142 stations on 99 streams tributary to Lake Superior and 83 stations on 56 streams tributary to Lake Michigan during 1962-65. Concentrations of aluminum, copper, and iron were not affected greatly by flow or season. Magnesium, calcium,...

This study is based on systematic seasonal bottom trawling between 3 and 50 fathoms (5.5 and 91.5 m.) from February to November 1964 and supplementary information from other experimental fishing at additional depths and with other gear. The seasonal depth distribution of eight common species is described, and temperature relations...

When the first alewife, Alosa pseudoharengus, was discovered in Lake Michigan near South Manitou Island on May 5, 1949, few people would have guessed that it would become the best known fish of the lake in less than two decades. Now it competes only with the coho salmon in...

The chemicals used to control the sea lamprey, Petromyzon marinus, in the Great Lakes have drastically reduced populations of larval lampreys in tributary streams. These larvicides are too costly and difficult to apply, however, in inland lakes, estuaries, and bays. Populations of sea lampreys in these areas constitute...

No abstract available....

A possible glacial boulder of undeformed and unmetamorphosed siltstone containing Middle Pennsylvanian plant fossils was recovered from the Bronx. The rock cannot be explained by known geologic relations and suggests the possibility of undetected outliers of Pennsylvanian rocks in the Hudson valley....

Fish brains were homogenized in an all-glass Potter-Elvehjem-type tissue grinder in 40% sucrose solution. The homogenate concentration was 10 brains/ml for both the bluegill and channel catfish. The brei was centrifuged at 34,700 g for 30 min at 5 C, and 30 J.lliters of the supernatant were used per column...