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and in some cases gemmulate. It is composed oftwo layers and includes radial channels and verysmall cavities with dark contents. The cavitiesare in the exospore outer layer, mostly arrangedalong the contact surface with the inner layer.They are tangentially aligned with respect to theinner exospore surface. The perispore is c.a.270 nm thick. It is composed of one to severalstrata and has irregular, spaced concentrations ofdense materials. Globules of different sizes, freeor fused together and covered with the perisporewere observed. The sporoderm organization andstructure are similar in the three genera studied.Nevertheless, differences in spore size, generalmorphology and the wall thickness were found.2008040063孢 粉 术 语 表 = Glossary of pollen and spore terminology.( 英 文 ). Punt W; Hoen P P; BlackmoreS; Nilsson S; Le Thomas A. Review of Palaeobotanyand Palynology, 2007, 143(1-2): 1-81The glossary of pollen and spore terminologywas first presented to the international palynologicalcommunity as the final outcome of theWorking Group on Palynological Terminologyat the 8th International Palynological Congressin Aix-en-Provence in 1992. It became widelyaccepted as reference guide for palynologists toassist in the preparation of accurate and consistentdescriptions of their material. It also servesas a practical source of information for nonspecialistswho wish to understand the meaningof the large number of existing palynologicalterms.2008040064白 垩 纪 - 第 三 纪 鹰 粉 植 物 地 理 区 内 孢 粉 植 物 群的 扰 动 和 绝 灭 = Cretaceous-Tertiary palynofloralperturbations and extinctions within theAquilapollenites Phytogeographic Province. ( 英文 ). Sweet A R; Braman D R. Canadian Journalof Earth Sciences, 2001, 38(2): 249-269A combination of detailed, intermediate andlarge scale stratigraphic perspectives is necessaryto understand the driving mechanisms forfloral change across the Cretaceous-Tertiary (K–T) boundary, because short-term physical andbiotic events occur within longer term trends.Most Maastrichtian palynofloral extinctionshave been identified within the northern circumpolar,supra-continental, Aquilapollenites Province.In mid-continental North America, thepresence of a physically defined K–T boundaryprovides opportunities to examine contemporaneousterrestrial palynofloras over a latitudinal(also approximately paleolatitudinal) distance of3200 km. Seventy-five percent of last appearancesoccur before the K–T boundary at highlatitudes and must have been caused by ongoingterrestrial processes. Palynofloral events directlyassociated with the K–T boundary include bothlocal last appearances, and inferred extinctions,and synchronous and diachronous changes inrelative abundances. Two different styles of factorsare reflected in these events. The first, possiblyattributable to chemical or other profoundatmospheric perturbations associated with theworldwide distribution of the "fireball" layer ofthe K–T claystone, resulted in extinctions of angiospermwith a zoophilous pollination strategy.The second factor, possibly reflecting energyreleased during the deposition of ballisticallytransported impact debris or hackly (ejecta) layerof the boundary claystone, resulted in the selective,northward-attenuating removal of the canopyvegetation, best documented for southwesternCanada, which was succeeded by a ferndominatedvegetation in mid-continental NorthAmerica. These consequences of the boundaryevent were mediated by independent, preexistingcircumstances: climate (regional and throughtime), local depositional environment, and ongoingbackground extinctions and origins.2008040065北 太 平 洋 东 北 部 阿 拉 斯 加 湾 大 洋 钻 孔 计 划 项目 887 井 位 中 更 新 世 至 全 新 世 孢 粉 地 层 =Middle Pleistocene to Holocene palynostratigraphyof Ocean Drilling Program Site 887 in theGulf of Alaska, northeastern North Pacific. ( 英文 ). Marret F; Vernal A D; Pedersen T F;McDonald D. Canadian Journal of Earth Sciences,2001, 38(3): 373-386A palynological investigation was undertakenon the upper 29m of sediment at Ocean DrillingProgram (ODP) Site 887, spanning the last 430000 years (i.e., isotopic stages 12 to 1). Pollenand dinocyst assemblages reveal a majorecostratigraphical boundary at the Middle–LatePleistocene transition. The Middle Pleistocenepollen data document the occurrence of a spruceforest vegetation in the source area, likely locatedon the adjacent Alaskan coast, whereas theLate Pleistocene is marked by higher inputs ofpine, shrub, and herb taxa, suggesting predominantinputs from a more open landscape. TheMiddle Pleistocene is characterized by a lowdiversity in dinocyst assemblages, which aredominated by Operculodinium centrocarpum,whereas the Late Pleistocene is marked by thesignificant occurrence of Pentapharsodiniumdalei, Pyxidinopsis reticulata, and by high percentagesof Brigantedinium spp. Such assemblagessuggest open oceanic and cool temperateconditions during the Middle Pleistocene, changingtoward generally colder and less saline conditionsduring the Late Pleistocene. In addition,large fluctuations in the dinocyst assemblages21