A NEW SPECIES OF ZOSTEROPHYLLUM FROM THE EARLY DEVONIAN OF NEW BRUNSWICK

A new species of Zosterophyllum, Z. divaricatum Gensel, is described from the late Early Devonian (Emsian) of northern New Brunswick, Canada. It is a Platyzosterophyllum type, consisting of slender sometimes bifurcating axes with laterally borne sporangia oriented to one side of the axis. The species is distinctive in that axes bifurcate within fertile regions and in sporangium shape and attachment. Aspects of the morphology of axis and sporangium cuticle, tracheids, and spores are presented and considered in relation to comparable features in other Zosterophyllum species. Associated vegetative axes exhibiting H- and K-branching patterns and also cuticular features similar to the fertile specimens are described and it is suggested that they may represent parts of the same plant. Zosterophyllum divaricatum is most similar to Z. llanoveranum, Z. fertile, and Z. spectabile, and also resembles Rebuchia ovata to some extent. Z. divaricatum offers considerable information on variation within one species concerning sporangium shape, attachment, and distribution and expands the known diversity of Platyzosterophyllum types.     

PTERYGOTUS ANGLICUS AGASSIZ (CHELICERATA: EURYPTERIDA) FROM ATHOLVILLE, LOWER DEVONIAN CAMPBELLTON FORMATION, NEW BRUNSWICK, CANADA

Abstract:  Specimens of the large eurypterid Pterygotus from the Early Devonian Campbellton Formation outcropping at Atholville, New Brunswick, are identified as Pterygotus anglicus Agassiz. The locality, in the Atholville beds near the western end of the Campbellton Formation exposure, is best known for its vertebrate fauna of ostracoderms, arthrodires, acanthodians and chondrichthyans, first described in 1881. Although a significant series of pterygotid fossils was acquired by the Natural History Museum, London, in 1892, it received little attention. A few small specimens from the Geological Survey of Canada collections were named Pterygotus atlanticus by Clarke and Ruedemann, considered here to be an invalid taxon. They suggested that P. atlanticus might turn out to be a small specimen of P. anglicus . The new material described here, including one relatively complete individual, confirms their suspicions and provides evidence of Pterygotus anglicus in the Lower Devonian of North America.     

THE CUTICLE OF DREPANOPHYCUS SPINAEFORMIS,A LONG-RANGING DEVONIAN LYCOPOD FROM NEW YORK AND EASTERN CANADA

The presence of paracytic stomata and paired guard cells on specimens presumed to be Drepanophycus spinaeformis Göppert from eastern Canada and New York State supports the conclusion of Banks and Grierson that the species is not a reliable index of Lower Devonian strata. The interpretation of stomatal morphology demonstrates that the species lived in Early, Middle, and Late Devonian time and that slender specimens are distinct from zosterophylls such as Sawdonia that had anomocytic stomata and a single guard cell. Knowledge of the stomata also permits a reinterpretation of the stomatal apparatus as first described by Lang. Siegenian specimens of the genus apparently represent the oldest occurrence of paired guard cells and of paracytic stomata.     

早泥盆世始叶蕨（新属）及叶子起源的讨论

本文报道了滇东南文山地区下泥盆统坡松冲组（西根阶）地层中一陆生植物新属,种－纤细始叶蕨（Eophyllophyton bellum gen.et sp.nov),植物体矮小,多次二叉分枝,远端枝二列互生长出次一级二叉分枝为主的末级枝,枝系起源叶顶生成侧生,多次分叉,缩合,扁化,蹼化并部分并合,生殖单位可下垂,由二枚顶端内卷的孢子叶组成,孢子囊圆至肾形,沿远,端加厚带开裂,成列侧生在孢子叶相对面的叶轴上,上述特征表明新植物远比同期的莱尼类,三枝蕨类和工蕨类复杂和进化,并显示出和工蕨类的某些亲缘关系,文内还探讨了枝系起源叶（大型叶）的发生和演化。     

云南沾益中泥盆世小肢鱼(Microbrachius)一新种

本文记述胴甲鱼类(Antiarchi)小肢鱼(Microbrachius)的一新种——中华小肢鱼(M.sinensis sp.nov.),发现于云南沾益中泥盆世曲靖组上部,这是小肢鱼化石在中国及亚洲_的初次发现,具有重要的生物地层和生物地理学意义。     

云南曲靖地区下泥盆统小肢鱼(Microbrachius)化石的新发现

记述了胴甲鱼类（ａｎｔｉａｒｃｈｓ）。肢鱼一新种,穿洞小肢鱼（Ｍｉｃｒｏｂｒａｃｈｉｕｓ ｃｈｕａｎｄｏｎｇｅｎｓｉｓｓｐ．ｎｏｖ．）。该化石发现于云南曲靖下泥盆统上部穿洞组,其时代大致与埃姆斯期（Ｅｍｓｉａｎ）相当。新种在以下 ３点与中华小肢鱼（Ｍ． ｓｉｎｅｎｓｉｓ）明显不同： １）个体明显小于中华小肢鱼;２）新种前中背片为三边形,举穴宽;３）新种纹饰在背甲上由纵向排列细而密的嵴组成。新种由于具有较大的中腹片和嵴状纹饰上没有启状突起,因而与小肢鱼的属型种Ｍ． ｄｉｃｋｉ不同。     

FUNGAL REMAINS IN THE DEVONIAN TRIMEROPHYTE PSILOPHYTON DAWSONII

Fungal reproductive structures were found within aerial axes of the Late Devonian trimerophyte, Psilophyton dawsonii Banks, Leclercq and Hueber from Quebec, Canada. Specimens are spherical to oval, up to 175 μm in maximum diam, and exhibit two distinct wall layers. They are restricted to the inner cortical region of infected axes. The fungal bodies resemble species of Palaeomyces from the well-known Rhynie Chert flora, and are also similar to the chlamydospores commonly found in Pennsylvanian coal ball plants. Among extant organisms they are most similar to oomycetous oogonia and endogonaceous chlamydospores.     

记利沃鱼(Livosteus)—新种

详细记述了发现于云南武定早泥盆世晚期利沃鱼(Livosteus)的新材料.依据其特征,建立一个新种.这是该属除在拉脱维亚以外在世界上的第二个种,因此具有重要的古生物地理意义.     

记陕西西安简獏一新种

<正> 最近,在整理标本时发现一獏类不完整头骨。经研究应为简獏属一新种。标本为1965年古脊椎所蓝田野外工作队在陕西省西安市红庆堡沟阴坡村“白鹿原组”地层内采得(野外号:65008)。现记述如下: 奇蹄目 Perissodactyla Owen,1848 獏超科 Tapiroidea Gill,1872 脊齿獏科 Lophialetidae Radinsky,1965 简獏属 Simplaletes Qi,1980 西安简獏 Simplaletes xianensis sp.nov.     

滇西早泥盆世大瓣鱼科(Macropetalichthyidae)化石的发现

<正> 泥盆纪的大瓣鱼化石目前除在南美和非洲尚未发现外,在全球其他各洲分布甚为广泛.它的分布时代可由早泥盆世延续到晚泥盆世.据统计目前发现的该科化石已达12个属.我国目前发现的大瓣鱼科化石共有5个属种,分布于华南的下、中泥盆统,主要发现于下泥盆统.     

广西早泥盆世一新型胴甲鱼化石并初步探讨其系统分类位置

本文描述的胴甲鱼化石标本,采自广西象州大乐早泥盆世地层.化石系内、外模,但保存非常完整,包括自然连接的头部、躯干、胸鳍及躯甲后的尾部.头甲、躯甲的特征较为接近星鳞鱼 (Asterolepis) 的特征,而某些特征又与云南鱼 (Yunnanolepis) 类似.胸鳍分为近节和远节,鳍片排列近似欧洲的翼甲鱼 (Pterichthyodes) 型的胸鳍.根据头甲、躯甲及胸鳍的特征,笔者建立了一新属、新种——Liujiangolepis suni gen. et sp. nov.,代表胴甲鱼类中—新科——Liujiangolepidae fam. nov..文中对新属种的胸鳍结构和新属种在胴甲鱼类中的分类位置做了初步探讨.     

A NEW GENUS AND SPECIES OF LYMNAEIDAE FROM THE LOWER FRANKLIN RIVER, SOUTH WESTERN TASMANIA, AUSTRALIA

The shell and anatomy of a new genus and species of Lymnaeidae,Kutikina hispida, are described from the Franklin River, S.W.Tasmania and the implications of this discovery, along withthe origins and relationships of the Australasian Lymnaeidae,are discussed. The new species lives attached to submerged limestonerock, has a very expanded shell aperture and, uniquely, theperiostracum bears short hairs. In addition there are apomorphicradular and anatomical characters separating this genus fromother lymnaeids. The new genus is compared with the other nativeAustralian Lymnaeidae. It is suggested that the taxonomy ofthe only other native Tasmanian species of Lymnaeidae, Austropepleatomentosa, a species widely distributed in temperate Australiaand in New Zealand, requires reexamination. Alternative hypothesesrelating to the zoogeography of the southern members of thefamily are discussed in relation to this taxon and the Recentgenus-group taxa of lymnaeids are listed in an Appendix andtheir differences from the new genus noted. (Received 20 June 1996; accepted 17 January 1997)     

A NEW BRACHYTHORACID ARTHRODIRE FROM THE DEVONIAN OF DICKSON LAND, VESTSPITSBERGEN

A brachythoracid anterior dorsolateral plate from the Devonian of Dickson Land is described as Arctonema crassum n.g., n.sp. In discussing the systematic position of this new genus, which may belong to the Holonematidae, remarks are given on the system of lateral lines on the anterior part of the trunk in coccosteids and holonematids. It is shown that even the posterior ventrolateral plate in some coccosteomorphs may exhibit lateral line grooves.     

湖南晚泥盆世短胸节甲鱼类一新属

本报道的鱼类化石产自湖南石门大京州的上泥盆统写经寺组。在中国泥盆纪地层分区上,化石产地属于华南区的湘、鄂、川交界分区(侯鸿飞等,1988)。该分区泥盆系为一套厚度不超过500m的近岸海相碎屑岩沉积,仅发育中泥盆统上部至上泥盆统(图1),并普遍超覆在志留系温洛克统之上,以角度不整合伏于石炭系或二叠系之下。上泥盆统分两个组,从下而上分别为黄家磴组和写经寺组。黄家磴组系杨敬之、穆恩之(1953)创立,标准地点在湖北长阳马鞍山东端的黄家磴。岩性为砂岩夹少量页岩,植物化石丰富,并含有误订为植物化石的湖北长阳鱼(Changyanophyton hupeiense Sze,1952)。根据植物化石组合面貌,黄家磴组的时代被认为是晚泥盆世早期。写经寺组是谢家荣、刘季辰(1927)创立的。岩性分为二段：下段以泥灰岩为主,含Yunnanella abrupta、Yunnanellina triplicata等腕足类化石;上段以砂页岩为主,含植物化石,其组合面貌除大致与黄家磴组相似外,还有一些新的分子,如Leptophloeum guanzhuangense、Cyclostigma hunanense等。根据动、植物化石群的性质,写经寺组的时代大致与法门期早期相当。多年来,在这一分区的泥盆纪地层里,很少鱼类化石。杨敬之、穆恩之(1953)曾提及在湖北长阳写经寺组底部发现的鱼化石,这些鱼化石与腕足类Yunnanella、Tenticospirifer等共生,但种属并未定出。已记述过的鱼化石只有湖北长阳黄家磴组的长阳鱼(潘江,1962)。     

辽西下白垩统九佛堂组尾羽龙类—新属(英文)

记述了一件采自辽西热河群九佛堂组一新的窃蛋龙类:义县似尾羽龙(Similicaudipteryx yixianensis gen.et sp.nov.),并依据其和尾羽龙属的相似特征,及其匕首状的尾综骨,肠骨、踱骨和脚趾的形态等将其归入窃蛋龙类的尾羽龙科,但其所具有的一些特征也不同于该科已建立的尾羽龙属,如尾综骨的形态和较大的个体等。该化石具有许多典型的窃蛋龙类的特征,如短尾、较短的前肢等,有别于其他窃蛋龙类的特征还包括耻骨和肠骨的长度比为1.46,背椎上发育2个大而深的椎体下突、背椎侧部具孔等。义县似尾羽龙是又一类具有真正尾综骨的恐龙,表明尾综骨这一曾经被认为是鸟类特有的结构可能是在恐龙中独自演化的。它具有一些进步的特征如具尾综骨等,但同时也具有一些原始的特征如5个愈合的荐椎,耻骨联合长,表明在窃蛋龙类中存在着特征的镶嵌进化现象。似尾羽龙与驰龙类、其他窃蛋龙类等恐龙一样,脚趾并没有对握,已有的证据说明完全的对握目前还只是出现于鸟类中。根据其短尾、中部收缩的趾骨和灵巧的身体等都表明它是一类适于快速奔跑的动物。目前为止,已知的尾羽龙类化石均发现于北票四合屯地区的义县组下部尖山沟层(段),距今约125Ma。新标本发现于义县西二虎桥地点,属于九佛堂组,距今约120Ma,这也是迄今为止在九佛堂组发现的惟一一件尾羽龙类化石,对研究早白垩世窃蛋龙类的演化和热河生物群恐龙组合的特征具有重要的意义。     

FUNGI FROM THE LOWER DEVONIAN RHYNIE CHERT: CHYTRIDIOMYCETES

Several different chytridiomycetes are described from the Lower Devonian (Siegenian) Rhynie chert. Included are both eucarpic and apparently holocarpic forms that occur in Palaeonitella, Aglaophyton, Lyonophyton, Horneophyton, and clusters of algal cells, as well as in the surrounding chert matrix. Holocarpic types consist of endobiotic sporangia, each characterized by one discharge tube. Sporangia can be traced from the thallus stage to the discharge of zoospores. Monocentric and polycentric eucarpic chytrids are associated with the miospores of Aglaophyton and various thick-walled fungal spores. In these forms the sporangia are variable in size and shape ranging up to 30 μm. Most appear to be inoperculate and there is evidence that the sporangium ruptured on the distal surface. Some contain zoospores with flagella. One operculate eucarpic form had parasitized the cellular gametophyte emerging from the proximal surface of an Aglaophyton spore. Several of the Rhynie chert chytrids are comparable with a number of extant forms (e.g., Olpidiaceae and Spizellomycetaceae), while others possess features that encompass several groups. These fossil fungi are discussed in the context of their interactions with other organisms in this Lower Devonian freshwater paleoecosystem.     

PITTING IN PSILOPHYTON DAWSONII,AN EARLY DEVONIAN TRIMEROPHYTE

Tracheids of Psilophyton dawsonii Banks, Leclercq, and Hueber 1975 from calcareous pebbles of late Early Devonian age on the Gaspé Peninsula, eastern Canada, are shown to have scalariform bordered and circular bordered pits. Macerated tracheids embedded in Spurr epoxy resin and sectioned at 2 μm; peels, ground sections, SEM and petrographic observations all indicate that interconnections between the scalariform bars are composed of secondary wall material and that the patterns produced are not artifacts of preservation. The interconnections produce a wide range of patterns from simple vertical strands, to reticula, to more extensive interconnections that outline circular openings. The circular openings result in scalariform bordered pits that are considered to be multiaperturate. P. dawsonii is believed to illustrate the most complex pitting yet demonstrated conclusively in Early Devonian time. Among trimerophytes P. forbesii, tracheids of P. charientos, and Hostinella from Röragen, Norway lack only the circular bordered pits.     

A NEW SPECIES OF MARSILEA FROM THE DAKOTA FORMATION IN CENTRAL KANSAS

Discovery of compression/impression megafossil material from the Cenomanian (mid-Cretaceous) in Kansas documents the occurrence of the genus Marsilea during this age. Only vegetative material has been found as complete plants; associated structures that may be fertile structures could belong to the genus also. This new fossil species extends the megafossil record of the genus back to the mid-Cretaceous when previously only megaspores attributed to the family occurred during this time. The fossil record of the heterosporous aquatic fern families is reviewed with emphasis on the Marsileaceae.     

新疆婆婆纳属一种

发表新疆婆婆纳属一新种