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Page 5481, results 137001 - 137025

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Not all publications have extents, not all extents are completely accurate
The megaspore genus Henrisporites from the Cretaceous of Massachusetts
Robert H. Tschudy
1975, Journal of Research of the U.S. Geological Survey (3) 15-20
A new megaspore species belonging to the genus Henrisporites was found in Cretaceous (probably Cenomanian) rocks from Massachusetts. Megaspores of Paxillitriletcs dakotaensis (Hall) Hall and Nicolson were found in the same rocks. This paper discusses the occurrence of these two megaspores in North America and describes Henrisporites angustus n. sp....
Ore grade, metal production, and energy
Norman J. Page, S. C. Creasy
1975, Journal of Research of the U.S. Geological Survey (3) 9-13
 Recent resource estimates have been stimulated by national concern over present and pending shortages of energy and mineral resources. Although some believe that the resource base of a commodity is the total amount in the crust, the energy consumption for mining and milling under present technology suggests that grades of...
Changes in the lake trout population of southern Lake Superior in relation to the fishery, the sea lamprey, and stocking, 1950-70
Richard L. Pycha, George R. King
1975, Technical Report 28
Commercial catch and effort statistics for 1929-70, samples of commercial catches in 1959-62, and records of examinations of all lake trout (Salvelinus namaycush) taken commercially in inshore waters of Michigan and Wisconsin in 1962-70 were the basis for descriptions of changes in the population in 1929-70. Abundance fluctuated cyclically and gradually...
Longevity of nonsprouting Ceanothus
Jon E. Keeley
1975, American Midland Naturalist (93) 504-507
Evidence is presented indicating species of Ceanothus in the subgenus Cerastes are generally longer-lived than species in the subgenus Euceanothus. It is proposed that this is due, at least in part, to the unique stem morphology of the former. The stems of these plants have a ribbed appearance which arises...
Thin-section electron microscopy of mature Myxosoma cerebralis (Myxosporidea) spores
P.D. Lunger, B.L. Rhoads, K. Wolf, M.E. Markiw
1975, Journal of Parasitology (61) 476-480
The morphology of purified, mature Myxosoma cerebralis spores was examined by thin-section electron microscopy. Surface architecture corresponded closely to that described in an earlier scanning electron microscopy study of this organism (Lom and Hoffman, 1971). A uniformly thick spore wall is composed of finely granular, electron-lucent material. Intrawall "valvoplasm" at...
Thoracic collapse as affected by the retia thoracica in the dolphin
Clifford A. Hui
1975, Respiration Physiology (25) 63-70
The carcass of a subadult female Delphinus was placed in a hyperbaric chamber and subjected to two simulated dives each equivalent to 69.7 m. In one dive the thorax was in its natural state, and in the other 100 ml of water had been injected into each pleural cavity. Various morphometric...
Productivity and flowering of winter ephemerals in relation to Sonoran Desert shrubs
William L. Halvorson, Duncan T. Patten
1975, American Midland Naturalist (93) 311-319
Ephemeral plant biomass and density on a Sonoran Desert hill near Cave Creek, Arizona, vary relative to shrub canopy type and shrub density. Higher shrub density associated with increased elevation appears to decrease both ephemeral biomass productivity and density, while ephemeral growth is enhanced under a shrub canopy if it...
Search for blood protozoans in the American woodcock
W.B. Krohn, J.R. Hynson
1975, Journal of Wildlife Diseases (11) 107-108
Smears were prepared from heart blood of 55 woodcock collected in central Maine between spring and fall, 1972 and 1973. Peripheral blood taken from the wings of 41 of these birds also was examined. Examination of stained films revealed no infected blood cells. Samples of heart blood from 35 of...
Utilization of Skylab (EREP) system for appraising changes in continental migratory bird habitat
E.A. Work Jr., D.S. Gilmer
1975, Technical Report CR-147542
The author has identified the following significant results. Surface water statistics using data obtained by supporting aircraft were generated. Signature extraction and refinement preliminary to wetland and associated upland vegetation recognition were accomplished, using a selected portion of the aircraft data. Final classification mapping and...