Early Devonian conodonts from Prince of Wales Island, southeastern Alaska

1984 ◽  
Vol 21 (12) ◽  
pp. 1415-1425 ◽  
Author(s):  
Norman M. Savage ◽  
George E. Gehrels

Early Devonian conodonts from 11 localities on Prince of Wales Island and adjacent small islands, southeastern Alaska, include Pandorinellina optima (Moskalenko), Pandorinellina exigua philipi (Klapper), Pandorinellina exigua exigua (Philip), Pandorinellina? boucoti (Klapper), Pelekysgnathus serratus Jentzsch, Pelekysgnathus cf. P. klamathensis Savage, Pelekysgnathus n. sp., Eognathodus sulcatus sulcatus Philip, Eognathodus sulcatus kindlei Lane and Ormiston, Eognathodus sulcatus n. ssp. A, Eognathodus sulcatus n. ssp. B, Ozarkodina eberleini Savage, Kimognathus alexeii Mashkova, Kimognathus n. sp. A, and Kimognathus n. sp. B. The occurrences indicate that Lower Devonian deposits are widespread on Prince of Wales Island. On Wadleigh Island, Zlichovian, and probably older, deposits underlie Eifelian beds of the Wadleigh Limestone, previously thought to include limestone only of Middle and Late Devonian age. The Early Devonian faunas of this part of southeastern Alaska contain species characteristic of Cordilleran North America. There are strong affinities with Nevada, eastern Australia, and central Asia, but lesser affinities with central and eastern Europe. Affinities with eastern North America and western Europe are relatively weak. Regional variations in conodont color alteration indices suggest that the southern half of Prince of Wales Island has a different post-Devonian thermal history from the northern half.

1987 ◽  
Vol 61 (4) ◽  
pp. 750-757 ◽  
Author(s):  
George C. Mcintosh

Two recently collected specimens of Bogotacrinus scheibei Schmidt, 1937, from the Devonian (Emsian–Eifelian) Floresta Formation of Colombia reveal that Bogotacrinus is a dicyclic camerate crinoid genus closely related to Pterinocrinus Goldring, 1923 (Lower–Upper Devonian of eastern North America and western Europe), and Ampurocrinus McIntosh, 1981 (Lower Devonian of Bolivia). The new diplobathrid camerate crinoid family Pterinocrinidae, characterized by species with low conical dicyclic cups and rami composed of compound, bipinnulate brachials, is herein proposed to accommodate these three genera. This family originated in western Europe and migrated into the Malvinokaffric and southern Eastern Americas Realms during the Early Devonian and into the northeastern Appalachian Basin by the Late Devonian.


Author(s):  
B. Guy Peters

Contemporary public administration reflects its historical roots as well as contemporary ideas about how the public bureaucracy should be organized and function. This book argues that there are administrative traditions that have their roots centuries ago but continue to influence administrative behavior. Further, within Western Europe, North America, and the Antipodes there are four administrative traditions: Anglo-American, Napoleonic, Germanic, and Scandinavian. These are not the only traditions however, and the book also explores administrative traditions in Central and Eastern Europe, Latin America, Asia, and the Islamic world. In addition there is a discussion of how administrative traditions of the colonial powers influenced contemporary administration in Africa. These discussions of tradition and persistence also are discussed in light of the numerous attempts to reform and change public administration.


1988 ◽  
Vol 25 (3) ◽  
pp. 442-453 ◽  
Author(s):  
T. E. Krogh ◽  
D. F. Strong ◽  
S. J. O'Brien ◽  
V. S. Papezik

The following new U–Pb dates are provided for zircons from volcanic and intrusive rocks of the Avalon Terrane of Newfoundland: Burin Group ophiolite (Wandsworth pegmatitic gabbro), [Formula: see text]; Marystown Group ash-flow tuff, [Formula: see text]; Rock Harbour Group rhyolite clast in conglomerate, [Formula: see text]; Harbour Main Group ash-flow tuff, [Formula: see text]; Harbour Main Group flow-banded rhyolite, [Formula: see text]; porphyritic rhyolite plug intruding Harbour Main Group, 632 ± 2 Ma; Holyrood Granite, [Formula: see text]; rhyolite dyke, Harbour Main Group, [Formula: see text]; and welded ash-flow tuff, "Grand Beach porphyry," [Formula: see text]. All of the dated zircons are simple, single-age populations with no trace of inheritance. These dates confirm that the ophiolitic Burin Group represents an older and separate event that correlates precisely with the Bou Azzer ophiolite of Morocco and that the Rock Harbour Group does not represent continental volcanism that preceded that event. The Rock Harbour, Marystown, and Harbour Main groups and the Holyrood Granite (632–608 Ma) are all part of the younger 650–550 Ma pulse of Pan-African orogenesis that affected a broad area extending through Africa, Asia, western Europe, southern England and Wales, and eastern North America. However, a shortage of high-precision dates throughout these terranes precludes very exact correlations and thus very exact interpretations in terms of specific tectonic or magmatic events. Although these dates require some revisions in the stratigraphy of the Newfoundland Avalon Terrane, they do not support suggestions that the Avalon Terrane comprises a "collage of suspect terranes." The age of the Grand Beach porphyry (394 Ma) places it squarely with the Acadian granites of the Appalachians and removes it from consideration as part of the Marystown Group.


1992 ◽  
Vol 6 ◽  
pp. 105-105
Author(s):  
Norman O. Frederiksen

Studies of Eocene angiosperm pollen floras in eastern North America (my work, especially in the eastern Gulf Coast) and western Europe (Boulter, Krutzsch) have shown significant differences in floral diversities between the two regions: in western Europe, maximum diversity was in the early Eocene and it decreased thereafter, in eastern North America, maximum diversity was in the middle part of the middle Eocene. The hypothesis presented here is that paleogeography was an important control on the diversity histories in the two regions: eastern North America was part of a large terrestrial landmass, whereas the terrestrial depositional basins of western Europe were on islands or peninsulas surrounded by the sea. Migrations between eastern and western North America were relatively easy, but migrations within what is now western Europe involved island-hopping, which explains distinct diachroneity of some angiosperm first appearances among different basins there. Western European basins were in contact with a large land mass during late Paleocene time but became isolated and smaller during the middle to late Eocene marine transgression. These changes resulted in decreased genetic exchange and increased probabilities of extinction due to (1) greater competition among species because of a reduced number of niches and (2) presence of small, isolated species populations, leading to local variations in extinctions, which probably explain the observed diachronism of taxon last appearances in different areas of Europe. Terrestrial climatic cooling in western Europe may be linked to decreasing contact between the NW European Tertiary Basin and the warm Tethys Seaway during the middle and late Eocene. In short, some combination of low environmental heterogeneity, geographic isolation, and long-term climatic deterioration probably caused the decrease in angiosperm diversity during the middle and late Eocene in western Europe.Several factors encouraged increasing or stable diversity in eastern North America but were far less effective in western Europe: (1) Eastern North America underwent greater climatic fluctuations during the Eocene (thus, immigration of taxa with different climatic preferences took place at different times), whereas the islands and peninsulas of western Europe had more uniform, maritime climates. (2) Evolution and immigration of r-selected taxa in eastern North America were favored by distinct dry seasons at certain times during the Eocene and by repeated marine transgressions and regressions that created opportunities for evolution and immigration of r-selected plants on and to freshly exposed coastal plain. In contrast, the predominantly maritime climates of western Europe in the early and middle Eocene favored K-selected plants, which had fewer possibilities for evolution and which had greater difficulty in migrating because island-hopping taxa are mainly r-selected. (3) “Arcto-Tertiary” taxa adapted to cooler climates lived and evolved in the uplands of the Appalachian Mountains, whereas western Europe was relatively flat in the Eocene –another example of its relative lack of environmental heterogeneity.


2011 ◽  
Vol 125 (3) ◽  
pp. 248
Author(s):  
Paul A. Heydon ◽  
Gavin C. Miller ◽  
Michael J. Oldham

Hairy St. John’s-wort (Hypericum hirsutum L.) is newly reported for Canada and North America based on two collections from the Toronto, Ontario, area. This perennial Eurasian herb has a large natural range from western Europe to western China. It grows in moist successional, edge, and meadow habitats. It should be looked for in such habitats elsewhere in eastern North America.


2019 ◽  
Vol 151 (5) ◽  
pp. 648-650
Author(s):  
Jean-Philippe Parent ◽  
Lori Bittner ◽  
Joel H. Kits

AbstractEuscelidius variegatus (Kirschbaum) (Hemiptera: Cicadellidae) is a leafhopper known to vector phytoplasmas in cultivated vines (Vitis vinifera Linnaeus (Vitaceae)) of western Europe. Its occurrence has been recorded in western North America more than 60 years ago, but so far not in eastern North America, including Canada. In the last 15 years, three specimens have been found in Ontario near and around vineyards. Here we report the first record of E. variegatus in Canada and eastern North America.


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