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nus, a new ichnospecies of Fuersichnus and ofMargaritichnus, and a new ichnotaxon Platicyteslioparadus. The geological and geographicaldistributions of many of these ichnotaxa areextended. Excellent examples of the compoundnature of Cruziana and Rusophycus are illustrated.Ichnotaxa are herein grouped into a Rusophycus,Margaritichnus, and Cruziana ichnocoenoses,each identified according to their paleoenvironmentaloccurrence. This is the firstdetailed description on ichnofossils reportedfrom Fish Hill, adding important palaeoenvironmentaland palaeoecological information towhat is previously known from these rocksbased on vertebrate fossils.2008040018西 班 牙 比 利 牛 斯 Ainsa-Jaca 盆 地 中 始 新 世 指示 深 海 环 境 的 特 征 性 的 遗 迹 化 石 = Trace fossilsas diagnostic indicators of deep-marine environments,Middle Eocene Ainsa-Jaca basin,Spanish Pyrenees. ( 英 文 ). Heard T G; PickeringK T. Sedimentology, 2008, 55(4): 809 - 844A quantitative study of trace fossil abundancein the Middle Eocene deep-marine clastic systems,Ainsa-Jaca basin, Spanish Pyrenees, showsthat they are powerful discriminators of submarinefan and related environments. Sixteen fanand related environments are recognized fromupper-slope gully to the distal basin-floor. Foreach environment, the degree of bioturbation(density), trace-fossil diversity, number of predepositionaland post-depositional trace fossils,as well as the number of graphoglyptid ichnospecieswere quantified. In the more laterallyconfined and channel-dominated Ainsa basin,there is a trend of increasing bioturbation intensityand trace-fossil diversity away from channel-axisto off-axis environments. In the moreunconfined and distal Jaca basin, there is a trendof increasing trace-fossil diversity and numberof pre-depositional trace fossils includinggraphoglyptids from the channel-lobe transitionto the fan-fringe. The trace-fossil assemblages ofthe Ainsa-Jaca basin are characteristic of a numberof sub-ichnofacies of the Nereites ichnofacies.In the distal Jaca basin, the Paleodictyonsub-ichnofacies occurs in the lobe-fringe andfan-fringe, whereas the distal basin-floor has atrace-fossil assemblage typical of the Paleodictyonsub-ichnofacies, but with a high proportionof post-depositional fodinichnia. Trace-fossilassemblages of proximal basin, axial, environmentsare characteristic of the Ophiomorpharudis sub-ichnofacies, whilst proximal off-axisenvironments, have a mixed Paleodictyon-Ophiomorpha rudis sub-ichnofacies trace-fossilassemblage.分 子 古 生 物 学2008040019解 译 后 口 动 物 的 系 统 演 化 : 分 子 的 、 形 态 的及 古 生 物 学 的 思 考 = Deciphering deuterostomephylogeny: molecular, morphological and palaeontologicalperspectives. ( 英 文 ). Swalla B J;Smith A B. Philosophical Transactions of theRoyal Society B: Biological Sciences, 2008,363(1496): 1557-1568Deuterostomes are a monophyletic group ofanimals that include the vertebrates, invertebratechordates, ambulacrarians and xenoturbellids.Fossil representatives from most major deuterostomegroups, including some phylum-levelcrown groups, are found in the Lower Cambrian,suggesting that evolutionary divergence occurredin the Late Precambrian, in agreementwith some molecular clock estimates. Molecularphylogenies, larval morphology and the adultheart/kidney complex all support echinodermsand hemichordates as a sister grouping (Ambulacraria).Xenoturbellids are a relatively newlydiscovered phylum of worm-like deuterostomesthat lacks a fossil record, but molecular evidencesuggests that these animals are a sister group tothe Ambulacraria. Within the chordates, cephalochordatesshare large stretches of chromosomalsynteny with the vertebrates, have a completeHox complex and are sister group to thevertebrates based on ribosomal and mitochondrialgene evidence. In contrast, tunicates have ahighly derived adult body plan and are sistergroup to the vertebrates based on the analyses ofconcatenated genomic sequences. Cephalochordatesand hemichordates share gill slits and anacellular cartilage, suggesting that the ancestraldeuterostome also shared these features. Genenetwork data suggest that the deuterostome ancestorhad an anterior–posterior body axis specifiedby Hox and Wnt genes, a dorsoventral axisspecified by a BMP/chordin gradient, and wasbilaterally symmetrical with left–right asymmetrydetermined by expression of nodal.2008040020从 直 接 发 育 的 半 索 动 物 Saccoglossuskowalevskii 洞 察 后 口 动 物 演 化 分 子 成 因 =Molecular genetic insights into deuterostomeevolution from the direct-developing hemichordateSaccoglossus kowalevskii. ( 英 文 ). Lowe CJ. Philosophical Transactions of the Royal SocietyB: Biological Sciences, 2008, 363(1496):1569-1578Progress in developmental biology, phylogenomicsand palaeontology over the past fiveyears are all making major contributions to along-enduring problem in comparative biology:the early origins of the deuterostome phyla. Recentadvances in the developmental biology ofhemichordates have given a unique insight into6