The Genus Coleosporium in the North-Western United States

Mycologia ◽  
1925 ◽  
Vol 17 (6) ◽  
pp. 225 ◽  
Author(s):  
James Robert Weir
1999 ◽  
Vol 26 (14) ◽  
pp. 2171-2174 ◽  
Author(s):  
Terje K. Berntsen ◽  
Sigrún Karlsdóttir ◽  
Daniel A. Jaffe

Parasitology ◽  
1927 ◽  
Vol 19 (1) ◽  
pp. 61-83 ◽  
Author(s):  
Harry M. Miller

1. Six new furcocercous cercariae from the north-western United States are described and comparisons with similar forms are made.2. On the basis of the structure ofCercaria tuckerensisspec. nov. and three cercariae reported in the recent literature it is possible to characterise more precisely the Elvae group, which now contains eight members.3. The execretory system ofCercaria elvaeMiller, 1923, was re-studied and found to differ from the original description. The bearing of this sort of error on Faust's use of excretory system formulae is touched upon.4.Cercaria burtiMiller, 1923, originally described from northern Michigan, is reported from San Juan Island.5. Certain features of the morphology and biology of the furcocercous cercariae are discussed in the light of this and other recent studies.6. Check List II of the furcocercous cercariae, with eighteen larvae, is given.


Variations in Cenozoic volcanism in the Western United States correlate rather closely with changes in tectonic setting: intermediate-composition rocks and their associated differentiates were erupted through orogenic or fairly stable crust, whereas basaltic or bimodal basalt-rhyolite suites were erupted later— concurrently with crustal extension and normal faulting. Lower and middle Cenozoic continental lavas, erupted onto postorogenic terranes, are predominantly intermediate types (andesite to rhyodacite), commonly with closely associated more silicic ashflow sheets. Compositional zonations in individual ash-flow sheets, from rhyolite upward into quartz latite, record magmatic differentiation in underlying batholithic source chambers. The intermediate lavas probably represent the greater part of these batholiths and the ash-flow tuffs their differentiated tops. Continental volcanic activity of this type was most voluminous in the northwestern United States in Eocene time, but shifted southward in the Oligocene; contemporaneous sea-floor basalts occur in the Oregon-Washington coast ranges. Largely intermediate-composition calc-alkalic igneous suites, that become more alkalic toward the continental interior, are characteristic of most of the North and South American cordilleran belt. Similar volcanic associations are forming now around most of the Pacific margin where continental plates override oceanic crust along active subduction systems, marked by Benioff seismic zones and oceanic trenches. A similar subduction mechanism probably operated in the Western United States until late Cenozoic time. Analogy with chemical variations across active island arcs suggest that early and middle Cenozoic subduction occurred along two subparallel imbricate zones that dipped about 20° eastward. The western zone emerged at the continental margin, but the eastern zone was entirely beneath the continental plate, partly coupled to the western zone below the low-velocity layer. Predominantly intermediate-composition volcanism persisted throughout the Western United States until the initial intersection of North America with the East Pacific rise started the progressive destruction of the subduction system


2016 ◽  
Vol 43 (1) ◽  
pp. 95-108 ◽  
Author(s):  
Neal Woodman

The North American naturalist Constantine S. Rafinesque spent much of the year 1818 engaged in a solo journey down the Ohio River Valley to explore parts of what was then the western United States. Along the way, he visited a number of fellow naturalists, and he spent more than a week at the Henderson, Kentucky, home of artist and ornithologist John James Audubon. During the succeeding two years, Rafinesque published descriptions of new species that resulted from his expedition, including eleven species of fishes that eventually proved to have been invented by Audubon as a prank on the credulous naturalist. Less well known are a number of “wild rats” described by Rafinesque that include one recognized species (Musculus leucopus) and ten other, imaginary “species” fabricated by Audubon (Gerbillus leonurus, G. megalops, Spalax trivittata, Cricetus fasciatus, Sorex cerulescens, S. melanotis, Musculus nigricans, Lemmus albovittatus, L. talpoides, Sciurus ruber). Rafinesque's unpublished sketches of these animals provide important insight regarding the supposed nature of the animals invented by Audubon and ultimately published by Rafinesque.


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