Search Results

The immune response among fish, from a phylogenetic standpoint, presents a progressive pattern of increasing development. The cyclostomes have been shown to have only feeble immunologic responsiveness. One of their number, the hagfish, appeared to be totally lacking in the ability to actively acquire antibodies.Among the elasmobranchs, the sharks have...

Duplicate potassium-argon age determinations on each of three samples from widely separated localities indicate that the age of the Bishop Tuff, California, is about 0.7 million years. Two of the samples are from the basal ash fall that preceded the ash flow eruptions; one of...

One to three whole-rock samples from each of more than a dozen discrete plutonic intrusions in the east-central Sierra Nevada batholith have been analyzed for Sr87/Sr86 and Rb/Sr ratios to obtain information on initial Sr87 abundances.The initial Sr87/Sr86 ratios in the rock magmas forming this province appear to have been in the range...

The following summary of the U. S. Geological Survey gravity program in Washington, Idaho, Montana, and Wyoming is one of a series of short papers that outline Geological Survey gravity projects in the western United States. The substance of this summary is a list of references of published papers on U. S. Geological Survey gravity projects in the northwestern states together with an index map (Figure 1) showing the location of the project, the approximate a...

If I had to cite one fact about water in the United States which would be not only the most important but also the most informative, the one I would choose would k this: Over 50 percent of all the water presently being used in the United States is used...

The lower limit of abundance of sodium and potassium in ultramafic rocks is less than the threshold amount detectable by conventional analytical methods. By a dilutionaddition modification of the flame-spectrophotometric method, sodium and potassium have been determined in 40 specimens of alpine ultramafic...

Several characteristics of 20 strains of oxidative pseudomonads, all but one of which were isolated from freshwater fish, were determined. All strains oxidized glucose and gluconate, produced NH3 from 1 % peptone, grew at 6, 12, 20 and 30° and produced cytochrome oxidase. Lipase was produced by 17 of the...

Humper lake trout are one of the several races or subpopulations of lake trout in Lake Superior. This study is based on 3,705 fish collected on a reef south of Isle Royale near the eastern end. The mean lengths of humper trout from commercial gill nets were smaller than those...

Two new species of Microsporidea, Plistophora salmonae from steelhead and rainbow trout (Salmo gairdntri) and Plistophora crpedianar from gizzard shad (Dorosoma cepedianum) are described. Schizonts to spores of P. cepedianae were found at one time within the same cyst, while only sporonts and spores of P. salmonae were found within the cyst.An illustrated synopsis of the known Microsporidea of freshwater and...

A grab sample from a depth of 1675 m at a point south of Cape Cod contains early Eocene planktonic Foraminifera and is correlated with the Globorotalia rex zone of Trinidad. The assemblage indicates a depth comparable to that existing today. Regional relations suggest that the Cretaceous and Eocene deposits deepen...

The Northville (Michigan) Biological Station has been a center for study of the developmental morphology of coregonid fishes. This work requires the production of numerous individual series of lake herring, lake whitefish, and several species of chubs from parent fish of positively known identity. The offspring of individual...

In natural streams turbulent diffusion is one of the principal mechanisms by which liquid and suspended-particulate contaminants are dispersed in the flow. A knowledge of turbulence characteristics is therefore essential in predicting the dispersal rates of contaminants in streams. In this study the theory of diffusion by continuous movements for...

The Anchorage area, at the head of Cook Inlet in south-central Alaska, occupies 150 square miles of a glaciated lowland and lies between two estuaries and the Chugach Mountains. Two military bases are in the area; Anchorage is the largest city in Alaska and the chief transportation center for this...

The Redwood Falls area includes about 80 square miles in southwestern Minnesota and is about 100 miles west of Minneapolis and St. Paul. Its surface is a gently undulating glacial-drift plain, interrupted in part by the large Minnesota River valley and the tributary Redwood River valley. The drift plain was...

Space science has been called “the collection of scientific problems to which space vehicles can make some specific contributions not achievable by ground-based experiments.” Geography, the most spatial of the sciences, has now been marked as one of these “space sciences.” The National Aeronautics and Space Administration (NASA) is sponsoring...

Rigid plastic collars of one to three colors proved useful for recognition of individual Canada geese (Branta canadensis). The collars did not seem to affect the behavior of the geese, and there was little mortality caused by their use. In good light, bright colors are visible through a 20-power spotting...

Deposits of ferruginous nickeliferous lateritic soils formed by weathering in place of ultramafic rocks occur at several places in northwestern California and southwestern Oregon, mostly in the Klamath Mountains province. Most of the deposits have been derived from relatively fresh peridotite, although at least one...

This discussion of the lithology and microfauna of the clastic facies of the Ecocene and Paleocene rocks of Florida is based mainly on data obtained from the study of many cores taken in the Oil City corporation Walton Land and Timber Co. well 1, Walton County, Fla. Although the fauna...

Livetrapping of opossums at the Patuxent Research Refuge in Maryland over an 8-year period resulted in the capture of 224 opossums, with 541 trap records. The maximum recorded trap life was 29 months, and the greatest estimated age was 36 months. Opossums did not enter traps readily, and the average...

A total of 1,303 whitefish were marked with spaghetti streamer tags in Wisconsin waters off Lake Superior in November of 1959, 1960, and 1961 and June-July 1960. The fish tagged in June-July 1960 were mostly undersized (less than 17 inches long) whereas those captured on the spawning grounds and tagged...

The round whitefish, though rarely abundant, is widely distributed in northern waters. It is one of the least studied of the coregonines; the present report is but the second for Great Lakes waters. Commercial production in Lake Michigan has been tightly confined to the northern portion. The period 1924-30 showed...

This study is based on 1,023 whitefish, Coregonus clupeaformis (Mitchill)--819 in seven samples from five localitites in central Green Bay in 1948-49 and 1851-52 and 204 in a single 1948 collection from northwestern Lake Michigan proper. Records of age indicated unusual strength for only one year class--1943 which strongly dominated...

Isolations from 1000 Potamogeton pectinatus plants collected from six major stands in Back Bay, Virginia and 13 in Currituck Sound, North Carolina yielded Pythium spp. consistently and in relatively high frequency. Although specific determination of these isolates was unsuccessful, they were separated into three groups according to morphological and cultural...

This is the second in a series of interpretive reports on subsurface outflow from the ground-water basins of San Bernardino County, Calif., prepared by the U.S. Geological Survey in cooperation with the San Bernardino County Flood Control District. One principal purpose of the study was to estimate the ground-water outflow...

Many elements have one or more naturally radioactive isotopes, and several hundred other radionuclides have been produced artificially. Radioactive substances may be present in natural water as a result of geochemical processes or the release of radioactive waste and other nuclear debris to the environment. The Geological Survey has developed...