Cytotaxonomy of some Cirsium species of the eastern United States, with a key to eastern species

1969 ◽  
Vol 47 (8) ◽  
pp. 1257-1275 ◽  
Author(s):  
R. J. Moore ◽  
C. Frankton

The morphology and chromosome number of nine species of Cirsium of eastern North America are considered. Chromosome counts are presented for the first time for C. iowense, 2n = 18; C. lecontei, 2n = 32; C. nuttallii, 2n = 24, 28; C. repandum, 2n = 30; C. smallii, 2n = 34; C. engelmannii, 2n = 20; C. texanum, 2n = 22, 24; C. virginianum, 2n = 28. Additional chromosomes, possibly to be considered as accessories, were found in C. nuttallii, C. engelmannii, and C. texanum. These chromosomes render uncertain the number characteristic of these species. A key to the 26 native and introduced species found in Canada and the United States east of 100° west latitude is presented. The interrelationships of the eastern species and of the species of the western series Undulata are discussed.

1993 ◽  
Vol 83 (4) ◽  
pp. 1064-1080 ◽  
Author(s):  
G. A. Bollinger ◽  
M. C. Chapman ◽  
M. S. Sibol

Abstract This study investigates the relationship between earthquake magnitude and the size of damage areas in the eastern and western United States. To quantify damage area as a function of moment magnitude (M), 149 MMI VI and VII areas for 109 earthquakes (88 in the western United States, 21 in the eastern United States and Canada) were measured. Regression of isoseismal areas versus M indicated that areas in the East were larger than those in the West, at both intensity levels, by an average 5 × in the M 4.5 to 7.5 range. In terms of radii for circles of equivalent area, these results indicate that damaging ground motion from shocks of the same magnitude extend 2 × the epicentral distance in eastern North America compared to the West. To determine source and site parameters consistent with the above results, response spectral levels for eastern North America were stochastically simulated and compared with response spectral ordinates derived from recorded strong ground motion data in the western United States. Stress-drop values of 200 bars, combined with a surficial 2-km-thick low velocity “sedimentary” layer over rock basement, produced results that are compatible with the intensity observations, i.e., similar response spectral levels in the east at approximately twice their epicentral distance in the western U.S. distance. These results suggest that ground motion modeling in eastern North America may need to incorporate source and site parameters different from those presently in general use. The results are also of importance to eastern U.S. hazard assessments as they require allowance for the larger damage areas in preparedness and mitigation programs.


1990 ◽  
Vol 68 (10) ◽  
pp. 2065-2069 ◽  
Author(s):  
Ronald A. Brammall ◽  
John C. Semple

Chromosome number determinations were made from 218 populations of Solidago nemoralis collected throughout the range of the species in Canada and the United States. All individuals of ssp. decemflora were tetraploid (2n = 36; 28 populations); these came from the prairies and adjacent eastern deciduous forest states and provinces. The majority of the collections of ssp. nemoralis were diploid (2n = 18; 161 populations) and came from throughout the eastern deciduous forest region of eastern North America. Tetraploids (2n = 36; 29 populations) of ssp. nemoralis were less frequent and occurred scattered across the eastern and northern portions of the range of the subspecies. The cytotype distribution pattern of the two subspecies of Solidago nemoralis is representative of what appears to be a frequent evolutionary strategy in the goldenrods.


1946 ◽  
Vol 78 (3) ◽  
pp. 47-54 ◽  
Author(s):  
W. J. Brown

In the following notes, two European species, one a pest of Lilium, are recorded for the first time from North America; an European pest that was introduced into the United States is recorded from Canadian localities; and a Mexican species not noted previously from the United States is recorded from Texas. The five forms described as new belong to difficult groups in which the species show strong monophagous tendencies.


Zootaxa ◽  
2017 ◽  
Vol 4234 (1) ◽  
pp. 1 ◽  
Author(s):  
OWEN LONSDALE

The Liriomyza (Diptera: Agromyzidae) of Canada and Alaska is revised, with species keyed and illustrated, and new host and geographic records provided. Eighty one species are recognized, including 24 new to science: L. agrios, L. albispina, L. anatolis, L. aphila, L. apilaca, L. aquapolis, L. arenarium, L. atrassimilis, L. bicolumbis, L. charada, L. cracentis, L. elevaster, L. emaciata, L. fumeola, L. gibsoni, L. griffithsi, L. hilairensis, L. limopsis, L. mesocanadensis, L. pilicornis, L. pistilla, L. rigaudensis, L. taraxanox, L. taraxanuda, L. tryssos. Ten species known from the United States are recorded as new to Canada: L. artemisiae Spencer, L. assimilis (Malloch), L. baccharidis Spencer, L. helianthi Spencer, L. merga Lonsdale, L. minor Spencer, L. sabaziae Spencer, L. temperata Spencer, L. violivora (Spencer) and L. virgo (Zetterstedt). Palaearctic species new to North America include L. wachtli Hendel and L. flaveola (Fallén); while the latter species has been recorded in North America before, all previous records represent misidentifications. Hosts are recorded for the first time for L. balcanicoides Sehgal, L. minor Spencer, L. orilliensis Spencer and L. socialis Spencer. Galiomyza Spencer syn. nov. is included as a junior synonym of Liriomyza Mik, resulting in six new combinations. 


2019 ◽  
Vol 132 (3) ◽  
pp. 264-267
Author(s):  
Paul M. Catling ◽  
Brenda Kostiuk

The introduced Wormslug (Boettgerilla pallens Simroth, 1912) is reported from Quebec, Canada, for the first time, from two closely situated localities in Gatineau Park. It was previously reported from the Vancouver area of British Columbia and, very recently, from Newfoundland. Within the Americas, the species has been reported from northern California, Mexico, and Colombia, and, because it is easily overlooked, likely occurs elsewhere in North America, especially in the eastern United States. In Quebec, it was found in a natural Sugar Maple (Acer saccharum Marshall) woodland and an ornamental garden. Wormslug likely reached both sites with shrub plantings from commercial nurseries, probably quite recently, because the invasive spread of the species, worldwide, has occurred mostly during the last few decades. Although the woodland where it occurred is dominated by native plants, the gastropod fauna there is mainly introduced. Identification, characteristics, and ecology of Wormslug are discussed. The potential for impact on native soil and soil surface organisms, including native terrestrial slugs and snails, is noted.


1990 ◽  
Vol 64 (5) ◽  
pp. 857-857 ◽  
Author(s):  
Elsie Darrah Morey

William C. Darrah, educator, geologist, botanist, and historian, loved life, and he chose to share with others his genuine enjoyment of discovery and learning through his writing and teaching. His A Critical Review of the Upper Carboniferous Floras of the Eastern United States (1970) and nearly a hundred professional papers made his name familiar to many paleontologists in Pennsylvania and throughout the United States. It is interesting to note that early in his career Bill developed an interest in the early conifers, especially Walchia. At the time of his death, he had just completed a manuscript with Paul Lyons, “The Earliest Conifers in North America: Upland and/or Paleoclimatic Indicators?,” “which has been accepted for publication in PALAIOS. Most recently, having attended the International Geological Conference in the United States in 1933, Bill had hoped to present a paper on the Dunkard at the July 1989 IGC in Washington, D.C.


1969 ◽  
Vol 47 (3) ◽  
pp. 353-368 ◽  
Author(s):  
Robert R. Ireland

A taxonomic study was made of several North American taxa in the genus Atrichum. The primary emphasis was on the Canadian taxa and a key to the six species (A. altecristatum, A. angustatum, A. crispum, A. oerstedianum, A. selwynii, A. undulatum) and one variety (A. undulatum var. gracilisetum) of the country is presented. Atrichum oerstedianum, which has been confused with A. undulatum, is added to the moss flora of the United States and Canada. The distribution of A. crispum is clarified and a detailed study of the species revealed new morphological characters that are useful to distinguish it. A variety of A. undulatum, the var. altecristatum, is raised to the rank of a species and morphological and distributional data are given to support the status of A. selwynii as a distinct species. The first chromosome counts are reported for A. selwynii (n = 7) and A. altecristatum (n = 14). Detailed descriptions are provided for A. altecristatum, A. crispum, A. oerstedianum, and A. selwynii.


2020 ◽  
Author(s):  
Julien Chartrand ◽  
Francesco Salvatore Rocco Pausata

Abstract. The North Atlantic Oscillation (NAO) affects atmospheric variability from eastern North America to Europe. Although the link between the NAO and winter precipitations in the eastern North America have been the focus of previous work, only few studies have hitherto provided clear physical explanations on these relationships. In this study we revisit and extend the analysis of the effect of the NAO on winter precipitations over a large domain covering southeast Canada and the northeastern United States. Furthermore, here we use the recent ERA5 reanalysis dataset (1979–2018), which currently has the highest available horizontal resolution for a global reanalysis (0.25°), to track extratropical cyclones to delve into the physical processes behind the relationship between NAO and precipitation, snowfall, snowfall-to-precipitation ratio (S/P), and snow cover depth anomalies in the region. In particular, our results show that positive NAO phases are associated with less snowfall over a wide region covering Nova Scotia, New England and the Mid-Atlantic of the United States relative to negative NAO phases. Henceforth, a significant negative correlation is also seen between S/P and the NAO over this region. This is due to a decrease (increase) in cyclogenesis of coastal storms near the United States east coast during positive (negative) NAO phases, as well as a northward (southward) displacement of the mean storm track over North America.


2016 ◽  
Author(s):  
Chase Doran Brownstein

The fossil record of dinosaurs from the Early Cretaceous of eastern North America is scant, and only a few sediments to the east of the continent are fossiliferous. Among them is the Arundel Formation of the east coast of the United States, which has produced among the best dinosaur faunas known from the Early Cretaceous of eastern North America. The diverse dinosaur fauna of this formation has been thoroughly discussed previously, but few of the dinosaur species originally described from the Arundel are still regarded as valid genera. Much of the Arundel material is in need of review and redescription. Among the fossils of dinosaurs from this formation are those referred to ornithomimosaurs. Here, I redescribe ornithomimosaur remains from the Arundel Formation which may warrant the naming of a new taxon of dinosaur. These remains provide key information on the theropods of the Early Cretaceous of Eastern North America. The description of the Arundel material herein along with recent discoveries of basal ornithomimosaurs in the past 15 years has allowed for comparisons with the coelurosaur Nedcolbertia justinhofmanni, suggesting the latter animal was a basal ornithomimosaurian dinosaur rather than a “generalized” coelurosaur. Comparisons between the Arundel ornithomimosaur and similar southeast Asian ornithomimosaurian material as well as ornithomimosaur remains from western North America suggest that a lineage of ornithomimosaurs with a metatarsal condition intermediate between that of basal and derived ornithomimosaurs was present through southeast Asia into North America, in turn suggesting that such animals coexisted with genera having a more primitive metatarsal morphology as seen in N. justinhofmanni.


2000 ◽  
Vol 19 (1) ◽  
pp. 33-35 ◽  
Author(s):  
John Sinkankas

William Maclure (1763-1840) established a reputation as a geologist and mineralogist in the United States, based largely on his well-known geological map of eastern North America, published in 1809. This research note discusses the important library of over 5,000 scientific books amassed by Maclure. Many of these books are now in the collection of the Academy of Natural Sciences of Philadelphia. [Editor's note: The on-line catalog of the Academy's library is at http://www.acnatsci.org/library.]


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