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tor muscles in modern brachiopods occupy thisposition. The round gap between the median foldof the pseudodeltidium and groove on chilidiumis proposed as the point of emergence of thepedicle muscle. The tiny foramen, commonlysealed early in growth, is suggested to be part ofa neanic water-intake system, active before thegrowth of the cardinal process in ephebic shells.Once the cardinal process appeared, the foramenwas blocked. Recurring types of strophomenidornamentation, such as posteriorly steepenedrugae and checkerboard ornamentation, mayhave served as a plow to redistribute sediment asthe shell was pulled backwards along the pedicle.2008040340晚 奥 陶 世 北 美 Hiscobeccus 腕 足 动 物 群 的 演化 和 绝 灭 = Evolution and extinction of theNorth American Hiscobeccus brachiopod Faunaduring the Late Ordovician. ( 英 文 ). Jin Jisuo.Canadian Journal of Earth Sciences, 2001,38(2): 143-151The earliest rhynchonellid brachiopods weresmall-shelled and preferred cool-water conditionsin both siliciclastic and carbonate environments.Relatively large shells of Rhynchotremaevolved in mid-Caradoc time and rapidly becamewidespread in Laurentia. Hiscobeccusprobably evolved from Rhynchotrema during thelate Caradoc by developing a large, globular,strongly lamellose shell. The earliest form ofHiscobeccusshows transitional characteristicsbetween Rhynchotrema and typical Hiscobeccus,most notably in its nonglobular shell that iswrinkled by growth lamellae only on the anteriortwo thirds of the shell. By early Ashgill time,Hiscobeccus became widespread in NorthAmerican inland basins, although it remainedcommon in marginal carbonate platforms andbasins. During the Ashgill, Hiscobeccus, Lepidocyclus,and Hypsiptycha represented a distinctNorth American fauna, characterized by large,globular, and completely wrinkled shells. Thesemorphological features were adaptations to theshallow, well-circulated, epicontinental, tropicalseas with a soft muddy substrate. The gigantismexhibited by the Hiscobeccus Fauna is alsoshown by orthid and strophomenid brachiopods,gastropods, nautiloids, and trilobites. Extinctionof the HiscobeccusFauna was probably related toits narrow range of environmental tolerance,especially during the Gondwana continental glaciation,which brought a major global sea-leveldrawdown and lowered ocean temperature. Thecool-water Rostricellulaand Rhynchotrema wereuncommon in inland seas during the Ashgill andwere represented by several opportunistic speciesin the Anticosti Basin during the Hirnantianand Llandovery, and most of these preferredsiliciclastic-rich or deep-water shelf carbonateenvironments.2008040341德 国 贝 尔 吉 施 陆 地 上 泥 盆 统 弗 拉 斯 期 剥 鳞 贝属 和 相 关 无 洞 贝 腕 足 动 物 = Desquamatia andrelated atrypid brachiopods from the Frasnian(Upper Devonian) of Bergisches Land, Germany.( 英 文 ). Ma Xueping; Ebbighausen V; Becker RT. Canadian Journal of Earth Sciences, 2008,45(2): 121-134Tropical shallow-water deposits of the RefrathFormation (topmost Lower to lower part of MiddleFrasnian) of the Bergisch Gladbach area(Rhenish Massif, Germany) yielded diverse,well-preserved shelly faunas. New collectionsshow that there are in total over 30 brachiopodspecies, of which the Atrypida, Rhynchonellida,Spiriferida, and Athyridida orders are the mostdominant groups. Serial transverse sectionsshow that Pseudoatrypa schroeteri possessessmall dental cavities, and their spiralia have awhorl number ranging from 12-13 in ca. 29-30mm wide specimens to 15-16 in ca. 32-33mmwide specimens. Desquamatia (Seratrypa) pectinatahas slightly more numerous spiralialwhorls, from 14-15 in ca. 27mm wide specimensto 18 in ca. 35mm wide specimens. A new species,Desquamatia (Seratrypa) refrathensis, isdescribed based on material from the RefrathFormation in Refrath, near Köln (Cologne), eastof the Rhine River, Germany. It includes finelyribbed, longer than wide, moderate- to largesizedshells of Desquamatia, which possess tinydental cavities to nuclei and 20-21 spiralialwhorls in ca. 30mm wide and long specimens.2008040342贵 州 省 东 南 部 江 南 斜 坡 下 奥 陶 统 同 高 组 深 水动 物 群 的 向 岸 迁 移 = Onshore migration of adeep-water brachiopod fauna from the LowerOrdovician Tonggao Formation, Jiangnan Slope,southeastern Guizhou Province, South China.( 英 文 ). Zhan Renbin; Jin Jisuo. Canadian Journalof Earth Sciences, 2008, 45(2): 141-157Brachiopods from the lower Tonggao Formation(Floian, late Early Ordovician) of Sandu,southeastern Guizhou Province, represent adeep-water benthic shelly fauna from the JiangnanSlope facies of the South China paleoplate.The fauna contains 16 brachiopod taxa, withorthides, lingulates, and pentamerides being thecommon groups. Concurrent graptolites confinethe brachiopod fauna to the Tetragraptus approximatusand the Acrograptus filiformis biozones(early Floian). The first appearance datum(FAD) of several brachiopod genera, such asParalenorthis, Protoskenidioides, and Nereidella,in the Sandu slope facies is one or two grapto-109