Pollen morphology of Ligusticum (Apiaceae) in Canada

1985 ◽  
Vol 63 (10) ◽  
pp. 1880-1887 ◽  
Author(s):  
Richard J. Hebda

The pollen morphology of the four Canadian taxa of Ligusticum (L. calderi, L. canbyi, L. scothicum ssp. scothicum, and L. scothicum ssp. hultenii) was studied under the light microscope and compared with that of other Apiaceae common on the Pacific coast of British Columbia and adjacent Alaska. Ligusticum calderi and L. canbyi compose one pollen type with a subrhomboidal outline in equatorial view and a triangular outline in polar view with pores located at the apices of the amb. Endopores are X-, H-, or dumbbell-shaped. The L. scothicum type is rectangular in equatorial view and circular in polar view, with pores arranged on the circumference. Endopores are usually rectangular to oval. Ligusticum calderi pollen is larger and thus distinct from L. canbyi pollen. All other Apiaceae pollen types examined are distinct from the L. calderi type because their pores are positioned between the lobes of the amb and because of differences in other characters. Since L. calderi pollen is readily separated from other Apiaceae on the British Columbia coast, it can be used to study the history of this geographically restricted species and the possibly refugial species associated with it. The size differences between L. calderi and L. canbyi pollen suggest that they are distinct species.

1960 ◽  
Vol 92 (11) ◽  
pp. 826-834 ◽  
Author(s):  
A. F. Hedlin

The Douglas-fir cone moth has been reported causing damage to cones and seeds of Douglas fir for a number of years; reports of seed loss range from light to almost 100 per cent. The insect occurs throughout the range of the host in British Columbia, the Pacific Coast States, and the Rocky Mountains.Observations recorded here were made during 1957 and 1958 in the Cowichan Lake area of Vancouver Island, and 1959 in the interior of British Columbia.


1995 ◽  
Vol 11 (1) ◽  
pp. 1-18 ◽  
Author(s):  
Brian F. Atwater ◽  
Alan R. Nelson ◽  
John J. Clague ◽  
Gary A. Carver ◽  
David K. Yamaguchi ◽  
...  

Earthquakes in the past few thousand years have left signs of land-level change, tsunamis, and shaking along the Pacific coast at the Cascadia subduction zone. Sudden lowering of land accounts for many of the buried marsh and forest soils at estuaries between southern British Columbia and northern California. Sand layers on some of these soils imply that tsunamis were triggered by some of the events that lowered the land. Liquefaction features show that inland shaking accompanied sudden coastal subsidence at the Washington-Oregon border about 300 years ago. The combined evidence for subsidence, tsunamis, and shaking shows that earthquakes of magnitude 8 or larger have occurred on the boundary between the overriding North America plate and the downgoing Juan de Fuca and Gorda plates. Intervals between the earthquakes are poorly known because of uncertainties about the number and ages of the earthquakes. Current estimates for individual intervals at specific coastal sites range from a few centuries to about one thousand years.


2012 ◽  
Vol 81 (3) ◽  
pp. 371-403
Author(s):  
Denise Khor

In the 1930s and 1940s Filipino laborers, many of whom were en route to agricultural hubs on the Pacific Coast, packed into movie theaters owned by Japanese immigrants to view Hollywood and Philippine-produced films. These cultural encounters formed an urban public sphere that connected both sides of the Pacific. Filipino patrons remade their public identities and communities through their consumption of film and urban leisure in the western city. This article traces this localized history of spectatorship and exhibition in order to reconsider prevailing understandings of the history of the U.S. West and the rise of cinema and mass commercial culture in the early twentieth century.


1987 ◽  
Vol 61 (1) ◽  
pp. 70-100 ◽  
Author(s):  
W. P. Popenoe ◽  
L. R. Saul ◽  
Takeo Susuki

Seven previously described and seven new taxa of gyrodiform naticoids from West Coast Late Cretaceous–Paleocene age strata are discussed. Gyrodes (Gyrodes) dowelli White of Turonian age is a typical Gyrodes; G. robustus Waring from the Paleocene has the shape of Gyrodes s.s. but lacks the crenulations. G. greeni Murphy and Rodda, G. yolensis n. sp., G. quercus n. sp., G. banites n. sp., G. canadensis Whiteaves, G. pacificus n. sp., and G. expansus Gabb comprise the new subgenus Sohlella, which thus ranges from Cenomanian through Maastrichtian. Gyrodes robsauli n. sp. resembles “Polinices” (Hypterita) helicoides (Gray), and Hypterita is reassigned to the Gyrodinae as a subgenus of Gyrodes. Gyrodes onensis n. sp. of Albian age is similar to the G. americanus group of Sohl (1960). Three texa—Natica allisoni (Murphy and Rodda) of Cenomanian age and N. conradiana Gabb and N. conradiana vacculae n. subsp. of Turonian age—which have all been previously considered to be Gyrodes are placed in Natica. Well marked relict color patterns on N. conradiana and N. conradiana vacculae suggest that these naticids from northern California and southern British Columbia were tropical forms.Diversity of taxa and size of specimens are reduced at the end of the Turonian, suggesting a change in West Coast marine conditions at that time.


Sederi ◽  
2014 ◽  
pp. 47-68
Author(s):  
Colm MacCrossan

This article examines the textual framing of a cluster of items in Richard Hakluyt’s The Principal Navigations, Voyages, Traffiques and Discoveries of the English Nation (1598-1600) relating to the area on the Pacific coast of North America that Francis Drake named “Nova Albion.” Contextualised in relation to the colonial programmes of Sir Humphrey Gilbert and Sir Walter Ralegh, it explores how a variety of editorial techniques combine to encourage a particular understanding of the history of exploration in this region that privileges English territorial claims over those of Spain. What is revealed is a delicate negotiation of the tensions raised by Hakluyt’s use of pre-existing, mainly non-English materials to attempt to legitimise Drake’s actions by aligning them with the Spanish conquistadorial tradition, while at the same time down-playing the extent and significance of previous Spanish activity in that region.


Bothalia ◽  
1983 ◽  
Vol 14 (3/4) ◽  
pp. 849-856 ◽  
Author(s):  
M. L. Frean

Pollen grains of the Euphorbiaceae show a number of pollen types which can be clearly distinguished. Generally different genera are characterized by a specific pollen type.  Euphorbia obesa Hook. f. and Croton gratissimus Burch, subsp.  subgratissimus (Prain) Burtt Davy, represent two genera within the Crotonoideae with different morphology, each type characteristic for the respective genus. Taxonomically, the genus Euphorbia with apetalous flowers consisting of a naked pistil surrounded by several staminate flowers within a cyathium, is considered more advanced than the genus  Croton. In  Croton the inflorescence is a raceme with unisexual flowers. The floral whorls of the male show numerous anthers and both calyx and a showy corolla are present. Both genera are insect pollinated. In both  Euphorbia obesa and  Croton gratissimus the pollen wall in section shows columellae, a structure characteristic of angiosperms. However the present ontogenetic studies show that the formation of the columellae differs entirely in the two pollen types. The final stratification of the wall as well as the morphology of the grains differ and evaluation of the exine structure indicates that phylogenetically Croton pollen shows more advanced characters than  Euphorbia — contradicting the floral phylogeny. This study conducted at light and electron microscope level compares the two pollen types morphologically and ontogenetically, concentrating mainly on the formation of the exine which is tectate-perforate in the prolate tricolpate grain of Euphorbia obesa and semi-tectate in the anaperturate, spheroidal grain of Croton gratissimus. The aim of the study was to evaluate the significance of pollen characters in taxonomic and phylogenetic relationships within the Euphorbiaceae. The differing pollen morphology which is related to the taxonomic grouping of tribes within the subfamily (Crotonoideae) emphasizes diversity, which may result from physiological adaptation. The study shows that the same functional end may well be achieved in different ways and this may be a factor underlying the diversity in the heterogeneous family Euphorbiaceae.


1970 ◽  
Vol 38 (2) ◽  
pp. 115-118 ◽  
Author(s):  
Ilkay Öztürk Çali ◽  
Feyza Candan

Effects of Agri Fos 400 (Mono and di-potassium phosphanate), a fungicide widely used on tomatoes grown in greenhouses in Turkey against Phytophthora infestans were studied on the morphology and viability of tomato (Lycopersicon esculentum Mill.) pollens. The fungicide was applied on tomato plants at recommended dosage (4 ml/l water) and double the recommended dosage (8 ml/l water). The fungicide caused changes in the morphological structures of pollens. Some pollen morphological structures that are not observed in the control group were encountered in the pollens due to application of Agri Fos 400 in equatorial view at 8 ml/l and in polar view at 4 ml/l. Level of pollen viability decreased as the dosage increased.   Key words: Fungicide; Phytophthora infestans; Tomato; Pollen morphology; Viability DOI: 10.3329/bjb.v38i2.5134 Bangladesh J. Bot. 38(2): 115-118, 2009 (December)


1972 ◽  
Vol 29 (3) ◽  
pp. 337-339 ◽  
Author(s):  
C. R. Forrester ◽  
Alex E. Peden ◽  
R. M. Wilson

Two specimens of the striped bass (Morone saxatilis) were taken in British Columbia waters in 1971. One was taken off Port San Juan (48°30′N, 124°30′W) and one in Barkley Sound (48°58′N, 125°03′W). Previous most northerly published record for the Pacific coast was from Puget Sound, Washington.


2018 ◽  
Vol 87 (1) ◽  
pp. 150-172
Author(s):  
Katherine G. Morrissey

The following was the author’s presidential address at the annual meeting of the Pacific Coast Branch, American Historical Association, in Northridge, California, on August 4, 2017. The twentieth-century visual history of the U.S.-Mexico borderlands, la frontera, offers a rich set of representations of the shared border environments. Photographs, distributed in the United States and in Mexico, allow us to trace emerging ideas about the border region and the politicized borderline. This essay explores two border visualization projects—one centered on the Mexican Revolution and the visual vocabulary of the Mexican nation and the other on the repeat photography of plant ecologists—that illustrate the simultaneous instability and power of borders.


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