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Page 5826, results 145626 - 145650

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Gas chromatographic separation and quantitative estimation of barbiturate mixtures in solid dosage forms
J. L. Allen
1968, Journal of the Association of Official Analytical Chemists (51) 619-621
A gas chromatographic method has been described for the analysis of mixed barbiturates in solid dosage forms. Analysis on a 10% SE-30 column gave good separations for butabarbital, amobarbital, secobarbital, pentobarbital, and/or phenobarbital; amobarbital is not separated adequately from pentobarbital. An internal standard, mephobarbital, is used to minimize injection errors....
A surface tow net for collection of parasitic-phase sea lampreys
Frederick H. Dahl
1968, Progressive Fish-Culturist (30) 183-184
A STUDY OF MIGRATORY BEHAVIOR of parasitic sea lampreys (Petromyzon marinus) in the Great Lakes required a means of capturing lampreys for tagging and releasing in St. Marys River, Lake Huron. Smith and Elliott (1953) fished specially made gill and trap nets for sea lampreys, but stationary nets could not...
Distribution and abundance of the Japanese snail, Viviparus japonicus, and associated macrobenthos in Sandusky Bay, Ohio
David R. Wolfert, Jarl K. Hiltunen
1968, Ohio Journal of Science (68) 32-40
A survey of the macrobenthos of Sandusky Bay, Lake Erie, in June, 1963, provided information on the abundance and distribution of the introduced Japanese snail, Viviparus japonicus, which has become a nuisance to commercial seine fishermen. The abundance and distribution varied considerably within the bay; at the time of the...
Movements of adult lake trout in Lake Superior
Jerold F. Rahrer
1968, Transactions of the American Fisheries Society (97) 481-484
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...
Comparative embryology of five species of lampreys of the upper Great Lakes
Allen J. Smith, John H. Howell, George W. Piavis
1968, Copeia (1968) 461-469
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...
An electric beam trawl for the capture of larval lampreys
Alberton McLain, Frederick H. Dahl
1968, Transactions of the American Fisheries Society (97) 289-293
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...
An improved girthometer for studies of gill net selectivity
Richard S. Wydoski, David R. Wolfert
1968, Progressive Fish-Culturist (30) 62-64
Gill nets are effective for collecting samples of many fish species. These nets may be highly selective in their catch, depending on the mesh size or sizes used and on the size distribution and body shape of the fish in the population. Early studies related mesh selectivity to...
Two hermaphroditic alewives from Lake Michigan
Thomas A. Edsall, Margaret I. Saxon
1968, Copeia (1968) 406-407
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....
Seasonal depth distribution of fish in southeastern Lake Michigan
LaRue Wells
1968, Fishery Bulletin (67) 1-15
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...
Annulus formation on scales of four species of coregonids reared under artificial conditions
Walter J. Hogman
1968, Journal of the Fisheries Research Board of Canada (25) 2111-2122
Scales from known-age coregonids reared in the laboratory were examined to determine when annuli formed and to learn possible factors of their formation. Scales were taken monthly from marked fish for periods up to 21 months. Scales were also examined from fish that died and from preserved specimens of young-of-the-year...
Production of sea lamprey larvae from nests in two Lake Superior streams
Patrick J. Manion
1968, Transactions of the American Fisheries Society (97) 484-486
The life history of the landlocked sea lamprey, Petromyzon marinus, has been described by several authors, the two most recent of which are Applegate and Wigley. The only information on the production of larvae from nests of the sea lamprey was reported by Applegate, who counted the larvae from three...
The alewife
Stanford H. Smith
1968, Limnos (1) 12-20
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...
Daytime distribution of Pontoporeia affinis off bottom in Lake Michigan
LaRue Wells
1968, Limnology and Oceanography (13) 703-705
The vertical migration of the amphipod Pontoporeia affinis in Lake Michigan has been well documented by Wells, Marzolf, and McNaught and Hasler. Wells and Marzolf observed Pontoporeia off bottom only at night. McNaught and Hasler, however, found Pontoporeia above the bottom shortly after noon in a 24-hr study on 12...
Species succession and fishery exploitation in the Great Lakes
Stanford H. Smith
1968, Journal of the Fisheries Research Board of Canada (25) 667-693
The species composition of fish in the Great Lakes has undergone continual change since the earliest records. Some changes were caused by enrichment of the environment, but others primarily by an intensive and selective fishery for certain species. Major changes related to the fishery were less frequent before the late...
Design and construction of a dual recharge system at Minot, North Dakota
Wayne A. Pettyjohn
1968, Groundwater (6) 4-8
In 1965, a ground-water recharge facility was constructed and placed in operation to forestall an impending water shortage at Minot, North Dakota. The facility is unique in that the rate of recharge to a buried sand and gravel aquifer is augmented by perforating an overlying bed of clay using hydraulic...
On the quantitative inventory of the riverscape
Luna Bergere Leopold, Maura O’Brien Marchand
1968, Water Resources Research (4) 709-717
In the vicinity of Berkeley, California, 24 minor valleys were described in terms of factors chosen to represent aspects of the river landscape. A total of 28 factors were evaluated at each site. Some were directly measurable, others were estimated, but each observation was assigned to one of five categories...
Geology and ground-water resources of Fillmore County, Nebraska, with a section on chemical quality of the water
Charles Franklin Keech, V. H. Dreeszen, L. R. Petri
1968, Water Supply Paper 1839-L
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...
Electrophoretic separation of fish brain esterases
Charles O. Knowles, Suresh K. Arurkar, James W. Hogan
1968, Journal of the Fisheries Research Board of Canada (25) 1517-1519
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...
Some enzymatic properties of brain Acetylcholinesterase from bluegill and channel catfish
James W. Hogan, Charles O. Knowles
1968, Journal of the Fisheries Research Board of Canada (25) 615-623
Using a manometric technique an acetylcholinesterase (EC 3.1.1.7, acetylcholine acetyl-hydrolase) was demonstrated in brain tissue from the bluegill, Lepomis macrochirus Rafinesque, and the channel catfish, Ictalurus punctatus (Walbaum). The activities were 19 and 37 μmoles acetylcholine hydrolyzed/milligram protein per hour for the bluegill and channel catfish enzymes, respectively. The optimum substrate concentration for the hydrolysis...
Some effects of mirex on two warm-water fishes
Charles C. Van Valin, Austin K. Andrews, Lafayette L. Eller
1968, Transactions of the American Fisheries Society (97) 185-196
The effects of mirex on two species of warm-water fishes were studied in three experiments in which the fish were exposed either by feeding a mirex-treated diet, or by treating the holding ponds with a mirex formulation. Bluegills were used in the feeding experiment, where three different levels of mirex...
A preliminary report of a recently discovered aquifer at Sioux Falls, South Dakota
Kenneth D. Vaughan, Earl A. Ackroyd
1968, South Dakota Academy of Science Proceedings (47) 68-74
A hydrologic study of the Big Sioux aquifer system was begun July 1, 1966, by the U.S. Geological Survey, in cooperation with the City of Sioux Falls and the East Dakota Conservancy Sub-District.   Test drilling being done in the search for a southern outlet to the Big Sioux aquifer has...
Selected hydrologic data, San Pitch River drainage basin, Utah
G.B. Robinson
1968, Utah Basic-Data Release 14
The u.s. Geological Survey investigated the ground-water resources of the San Pitch River drainage basin during the period 1964- 67. The investigation was a cooperative project, financed equally by the Utah Department of Natural Resources, Division of Water Rights, and the Federal Government, and was a part of an investigation...