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y high Reynolds numbers, inducing the weakestbuoyancy within porcelaneous larger foraminifera.The highest buoyancy was recorded for thethree soritids, Parasorites orbitolitoides, Soritesorbiculus and Amphisorus hemprichii, becauseof their low test densities (ca 1·25) and the extremelyflat, biconcave, plate-like shape. Flattests, however, reduce traction and entrainmentfrom smooth surfaces. Within hyaline larger foraminiferat,the amphisteginids show thicklenticular(Amphistegina lobifera, A. radiata) tothin-lenticular tests (A. bicirculata, A. papillosa),influencing buoyancy. Here, high test densities(ca 1·8) decrease with growth in A. lobifera, A.lessonii and A. bicirculata, and remain constantin A. radiata and A. papillosa. Minimum velocitiesrequired for entrainment are lower for thicklenticulartests and higher for thin-lenticular tests.Test densities remain constant with growth in thecalcarinid Baculogypsina sphaerulata (ρ 1·78)and decrease slightly in Calcarina gaudichaudiiand Neorotalia calcar (starting at ρ1·85), all livingunder extreme hydrodynamic conditions.Density decreases the most in Baculogypsinoidesspinosus (starting at ρ1·8), resulting in higherbuoyancy through low Reynolds numbers. Tractionis promoted in spherical tests of Baculogypsinaand Baculogypsinoides. Within nummulitids,the thick-lenticular Palaeonummulitesvenosus (test density decreasing with size; startingat 1·78) is less buoyant, expressed in highReynolds numbers, but easily entrained. Thicklenticularjuveniles and extremely flat adultsdistinguish Operculinella cumingii, Heterosteginadepressa and the giant Cycloclypeus carpenteri.Test densities increase during growth,starting from ca 1·6 and attaining a maximum of1·8. Buoyancy is low in small tests and high inlarge tests, while entrainment velocities are reducedas the tests flatten. High buoyancy is alsoa characteristic of the entirely flat tests in Operculinaammonoides (from deeper regions) andPlanostegina operculinoides, which is expressedin the lowest Reynolds numbers within largerforaminifera.2008040298浮 游 有 孔 虫 长 期 演 化 过 程 中 受 环 境 影 响 的 周期 性 自 组 织 特 性 = Periodically forced selforganizationin the long-term evolution of plankticforaminifera. ( 英 文 ). Prokoph A; Fowler A D;Patterson R T. Canadian Journal of Earth Sciences,2001, 38(2): 293-308Wavelet transform and other signal analysistechniques suggest that the planktic foraminiferal(PF) long-term evolutionary record of thelast 127 Ma can be attributed to complex periodicand nonlinear patterns. Correlation of thePF extinction pattern with other geological seriesfavors an origin of the ~30 Ma periodicity andself-organization by quasi-periodic mantleplumecycles that in turn drive episodic volcanism,CO 2 -degassing, oceanic anoxic conditions,and sea-level fluctuations. Stationary ~30 Maperiodicity and a weak secular trend of ~100 Maperiod are evident in the PF record, even withoutconsideration of the mass extinction at the K–Tboundary. The 27–32 Ma periodicity in the impactcrater record and lows in the global sealevelcurve, respectively, are ~6.5 Ma and ~2.3Ma out of phase with PF-extinction data, althoughmajor PF-extinction events correspond tothe bolide impacts at the K–T boundary and inlate Eocene. Another six extinction events correspondto abrupt global sea-level falls betweenthe late Albian and early Oligocene. Selforganizationin the PF record is characterized byincreased radiation rates after major extinctionevents and a steady number of baseline species.Our computer model of long-term PF evolutionreplicates this SO pattern. The model consists ofoutput from the logistic map, which is forced at30 Ma and 100 Ma frequencies. The model hassignificant correlations with the relative PFextinctiondata. In particular, it replicates singularities,such as the K–T event, nonstationary2.5–10 Ma periodicities, and phase shifts in the~30 Ma periodicity of the PF record.2008040299南 大 洋 地 区 KH94-4-AMR-2PC 孔 更 新 世 放射 虫 分 布 和 系 统 分 类 = Distribution and taxonomyof Pleistocene radiolarians from KH94-4-AMR-2PC core of the Southern Ocean region.( 英 文 ). Sharmaa G K; Takahashib K. Palaeoworld,2008, 17(1): 57-82This paper presents first comprehensive accountof radiolarian taxa from the Pleistocenesequence of the Antarctic region. On the basis of54 samples from the piston core KH94-4-AMR-2PC, 71 well-preserved radiolarian species wereidentified and illustrated. Their systematics,morphological variability and distribution in thisSouthern Ocean region are given and also comparedwith similar data available from other regions.Ten new taxa are described in detail butare yet to be formally named. This study providesa more extensive database and new taxafor comparative studies of other parts of theocean sectors of the Antarctic region2008040300环 特 提 斯 东 北 部 上 Ypresian 腐 泥 层 有 孔 虫 古生 物 群 落 分 析 = Analysis of foraminiferal paleocoenosesfrom the upper Ypresian sapropeliclayers of the northeastern Peri-Tethys. ( 英 文 ).Stupin S I. Stratigraphy and Geological Correlation,2008, 16(2): 198-20397