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1.
SYNOPSIS. Tintinnida of the New York Bight (a bend in the coastline) were identified during the 1-year period August 1973–August 1974. Recurring genera included Stenosemella and Tintinnopsis; seasonal genera were mainly the hyaline Favella, Metacylis, and Helicostomella; exotic or unusual genera included Parafavella and Ptychocylis. Large size differences in loricae were found seasonally, related apparently, to water temperature.  相似文献   

2.
Eight new specimens and the holotype of Lepidocoleus sarlei Clarke, 1896 from Lagersta¨tten deposits within the Rochester Shale (Silurian, Wenlock) of New York are described to elucidate the morphology, function and construction of the scleritome. The material exhibits an unusual type of dorsal hinge with a pronounced antero-posterior displacement between the two sides. Two specimens have an aberrant sclerite on the right side of segment eleven. One tightly enrolled specimen may demonstrate a method of defence with the stronger protected dorsal side oriented outwards. The presence of a segmented body plan is suggested, based on requirements for a functional spiral enrolment. Distinct anterior and posterior morphologies together with the pattern of rugae provide valuable help in reconstructing disarticulated lepidocoleids.  相似文献   

3.
This paper presents evidence for what is believed to be the first reported case of pre-Columbian treponematosis in northeastern North America. The temporal position of the skeletal material, salvaged from a site in New York State, is determined on the basis of archeological evidence.  相似文献   

4.
A new genus of lycopods from the Devonian of New York State   总被引:2,自引:0,他引:2  
Drepanophycus colophyllus Grierson & Banks is transferred to llaskinsia Grierson & Banks on the basis of the morphology of its leaves and its anatomical structure. Slender, dichotomizing axes bear helically arranged leaves that are falcate, petiolate, simple, lanceolate and entire. A solid cylinder of metaxylem is surrounded by ridges of protoxylem. Pitting on tracheid walls is annular, helical, reticulate, scalariform to circular-bordered. This lycopod extends from early Givetian into early Frasnian time in the Catskill strata of eastern New York State. The effect of cleavage of fossiliferous rock on patterns observed on the exposed fossils and the bearing of recent research on the fossil history of lycopods are discussed.  相似文献   

5.
The evidence mainly involving graptolites is restated which supports an Upper Silurian (Ludlow) dating for a vascular flora containing Baragwanathia (Lycophytina) in Victoria, Australia.  相似文献   

6.
Scanning electron microscopy of polished, slightly etched rock surfaces of samples from the Silurian of Gotland, Sweden, revealed the presence of excellently preserved calcareous microfaunas and microfloras. This paper illustrates several morphotypes of calcareous micro-organisms of unknown biological affinity, attributed to the new family Ovummuridae. Specimens of Ovummurus duoportius Minoura and Chitoku, a problematical microfossil, which was first described from the Upper Pennsylvanian of Kansas, USA, were found in addition to comparable micro-organisms attributed to the following new taxa: Minourella gotlandica gen. et sp. nov., Arouxina pluricellata gen. et sp. nov. and Samtlebenella circumcamerata gen. et sp. nov. In addition, a few other problematical micro-organisms, probably belonging to the same family, are described under open nomenclature. The enigmatic microfossils are compared with other known calcareous organisms, their possible biological affinities are discussed, and the different stages of diagenetic alteration and destruction are illustrated.  相似文献   

7.
Fossilised traces of swimming amphibians, assigned to Batrachichnus delicatulus and Serpentichnus robledoensis igen. et isp. nov., are described from the Lower Permian of the Robledo Mountains, southern New Mexico. The B. delicatulus specimen is interpreted as a trackway of a small 'amphibian' (temnospondyl, nectridean, microsaur or juvenile embolomere) swimming straight ahead. S. robledoensis consists of repeated pes imprints separated by discontinuous, L-shaped imprints (body traces). It is interpreted as a trackway of an 'amphibian' swimming in a similar manner to the motion of a side-winding snake. The producer of S. robledoensis is more distinctive than in B. delicatulus , and is suggestive of the lysorophian Brachydectes . This is the first locomotory trace to be assigned to this 'amphibian' group.  相似文献   

8.
The age of Rock Units B1 and B2 of the Middle Silurian-Lower Devonian of Sahara (Algeria) is assessed and confirmed as late Homerian to ?earliest Lochkovian on the basis of moderately well preserved miospore assemblages. The data upon which this age assessment is provided by recent palynological studies in the Cantabrian Mountains (NW Spain), the type Wenlock area, Shropshire (England), south and south-west Wales, the Midland Valley of Scotland and the Ghadames Basin, Libya. Quantitative study shows that cryptospores decrease in number and variety upwards, laevigate miospores are prevalent and the representatives of the rugulate, crassitate genus Scylaspora are dominant. The occurrence and range of these species as well as other miospore taxa recorded during this study provide the basis for recognizing three miospore assemblage and one interval biozones, namely Scylaspora vetusta-Scylaspora kozlica, Chelinospora sanpetrensis-Cymbosporites triangulatus, Chelinospora hemiesferica and Scylaspopra radiata-Apiculiretusispora synoria. Of these biozones, two assemblage biozones are proposed as new. Core samples of Rock Unit B1 from borehole NGS-1 of the Triassic Province contain the oldest two miospore assemblage biozones. Rock Unit B2 from the boreholes GMD-2, ISS-1 (Tidikelt Plateau) and NGS-1 (Triassic Province) comprise the youngest two miospore biozones. The assemblage and interval biozones allow inter-regional correlation with latest Middle Silurian to probably earliest Devonian strata. The inadequacy of coverage of core samples result in the absence of critical palynological evidence, to determine the exact position of the base of the Ludlow, Pridoli and Lochkovian. Comparison with the zonal and sub-zonal divisions of Mid-Palaeozoic sequences from other parts of the world shows crucial differences in the distribution of the spore flora within Gondwanan and Euramerican regions during Pridoli and early Lochkovian. Six new miospore species namely Retusotriletes delicatus nov. sp., Scylaspora cymba nov. sp., S. distincta nov. sp., S. radiata nov. sp., S. undulata nov. sp. and Cymbosporites triangulatus nov. sp. are described. Three more possibly new miospore forms are described and illustrated but not specifically named.  相似文献   

9.
Stromatoporoidea are widespread in the Upper Ordovician and Silurian beds of the Kozhim River (western slope of the Subpolar Urals). Five new species Cystostroma prodigiosum sp. nov., Stylostroma flabellatum sp. nov., Labechiina arguta sp. nov., Ecclimadictyon faveolatum sp. nov., and Araneosustroma astroplexum sp. nov. are described.  相似文献   

10.
《Comptes Rendus Palevol》2014,13(6):483-488
The Chalonnes-sur-Loire outcrop is the most complete Llandovery section in the Ligerian domain (Armorican Massif, NW France); it displays a ca. 10 m-thick sequence of organic-rich black bedded cherts alternating with black graptolitic shales, which were deposited above glaciomarine diamictites of the Hirnantian glaciation. It is likely the black cherts accumulated under eutrophic waters, on the outer shelf part (distal offshore) of a Gondwanan margin, situated at intermediate to high latitudes of the Southern hemisphere. Hydrofluoric acid processing allowed the extraction of radiolarians; seven species are identified in the best preserved sample discovered so far. All seven are common species in tropical assemblages known from Alaska and Nevada, which are characteristic of the Orbiculopylorum assemblage, of Aeronian to early Telychian age. This age is in good agreement with independent age control from graptolites in the Chalonnes section, suggestive of an Aeronian age for the radiolarian-yielding level.  相似文献   

11.
The majority of the Wellesley College Herbarium (62, 193 specimens) has been intercalated into The New York Botanical Garden Herbarium (NY). Duplicated collections were distributed to other herbaria. Most specimens has been collected between 1850 and 1940. A brief history of the Wellesley Herbarium is given, and lists of the vascular plant type specimens and of some notable collectors of vascular plants are appended.  相似文献   

12.
The fourth series of the Silurian System in Podolia   总被引:1,自引:0,他引:1  
The Skala horizon of Podolia has been under discussion as a possible candidate for the stratotype of the fourth Silurian series (primary subdivision) in the international standard chronostratigraphical scale. After a brief survey of the history of investigation, the section through the basal boundary of the Skala horizon is fully documented. The lithostratigraphy, biostratigraphy, and correlation of the Skala horizon are then discussed.  相似文献   

13.
Olev Vinn  Mark A. Wilson 《Ichnos》2013,20(3):166-171
The distribution of Osprioneides is more environmentally limited than that of Trypanites in the Silurian of Baltica. Osprioneides probably occurred only in large hard substrates of relatively deepwater muddy bottom open shelf environments. Osprioneides were relatively rare, occurring in 4.7% of all stromatoporoid specimens in that environment, in contrast to small Trypanites-Palaeosabella borings, which occur in 88.4% of stromatoporoids and 88.9% of heliolitid corals. Osprioneides is reported only from the lower Sheinwoodian stromatoporoids of the exposed Silurian of Saaremaa (Wenlock to Pridoli). Osprioneides borings probably played a minor role in the general bioerosion in the Silurian of Baltica.  相似文献   

14.
The integration of the vascular plants from the Yuncker Herbarium (DPU) into the New York Botanical Garden Herbarium (NY) has been completed, and the curatorial work is summarized. The most notable vascular plant collections, with emphasis on the local collections from Indiana, are reported on and a list of the most prominent collectors is presented. An index to all collectors of vascular plants represented in the Yuncker Herbarium has been deposited in the New York Botanical Garden Library.  相似文献   

15.
记述了云南昭通早泥盆世布拉格期坡松冲组华南鱼目一新属、新种——剑裂甲鱼(Rhegmaspis xiphoidea gen.et sp.nov.)。新属的主要特征是:具有鱼雷形头甲,细长吻突,眶孔位于头甲腹侧位,鳃穴向头甲腹面弯曲,角、内角和腹环丢失。鉴于以上特征,新属被归到了包括鸭吻鱼和乌蒙山鱼在内的鸭吻鱼科。根据新材料提供的信息,修订了鸭吻鱼科,包括鸭吻鱼和乌蒙山鱼的鳃穴、腹环、角、内角等特征。裂甲鱼属是该地区发现的第一个具有流线形体型的盔甲鱼类,指示了该地区一些盔甲鱼类可能开始了一种营上底栖的生活方式,具有更加主动的取食行为。新属的发现不仅丰富了该地区华南鱼目的多样性,而且提供了盔甲鱼类在早泥盆世布拉格期通过占据新的生态位而发生的最后一次辐射演化的证据。  相似文献   

16.
Divergence of Silurian encrinurine trilobite clades from common ancestry may be modelled as hetero-chronic pattern. Comparing ontogenies of ancestral late Ordovician Encrinuroides and the descendant punctarus and uariolaris plexi of Silurian Encrinurus provides a test of this hypothesis. Heterochrony in the punctarus plexus is dissociated with respect to entire organisms, but regionally global throughout cranidia (paedomorphic states) and pygidia (peramorphic states). Regulatory dissociation may explain the apomorphous enrollment strategy of this group. The uariolaris plexus, for which a growth series of Balizoma dimitroui (Perry & Chatterton) provides ontogenetic data, shows a complex of peramorphic cephalic character states. Changes in developmental timing thus provide a mechanism by which morphologic and ecologic divergence of closely-related clades was catalyzed in the Llandovery encrinurine radiation. Paedomorphic and dissociated Lineages of the odontopleurid Leonaspis provide a comparable example of divergent heterochronic pattern associated with coexisting (in the same biofacies) species of comparatively recent common ancestry.  相似文献   

17.
Beyrichidiscus fecundatus n. gen. n. sp. is described from the Upper Silurian of Gotland, Sweden. The minute, isostrophically coiled mollusc exhibits profound allometry and is considered to have been a monoplacophoran on the basis of functional interpretation of apertural structures. A clam-like, semi-infaunal mode of life is suggested. A pair of prominent lateral swellings in the adult shell are interpreted as reflecting the location of the gonads.  相似文献   

18.
Current environmental challenges involve complex assessment and analysis of tradeoffs among differing criteria, expectations, and levels of certainty. Using multi-criteria decision analysis in combination with comparative risk assessment, a systematic and transparent framework can be created to integrate different types and sources of decision-relevant information. Although examples of decision analysis abound in the literature and academic efforts, its use within the practice of risk assessment and environmental management is still being established. This article provides an example of the use of decision analysis study that builds on a previous screening-level, comparative risk assessment of contaminated sediment from the New York/New Jersey harbor area. Using multi-criteria decision analysis, we explored the effect of different criteria weights, utility functions, and cost estimates on the ranking of seven contaminated sediment management alternatives. Values used in weighting decision criteria were surveyed from two interaction sessions with sediment management professionals.  相似文献   

19.
In order to investigate whether or not equivalents to modern calcareous plankton existed in Palaeozoic times, extremely well-preserved successions have to be investigated. The Silurian strata on Gotland (Sweden) are exceptionally well preserved because they have not experienced deep burial conditions and tectonic stress, due to their position on the stable Baltic Shield. Scanning electron microscope investigations of polished, slightly etched rock surfaces revealed the presence of a variety of calcareous micro- and nannofossils. Among these organisms, many can be termed 'calcispheres' (60–100 µm in diameter), whereas others due to their size range (nannofossils) are informally termed herein as 'nannospheres' (10–25 µm in diameter). The systematic attribution of these fossils is unknown ( incertae sedis ). Mesozoic calcispheres are usually attributed to calcareous cysts of dinoflagellates following comparisons of ultrastructure with modern species. The abundance of different calcispheres in the Silurian sediments of Gotland and the observation that many of the calcareous microfossils occur in distinctly different facies as well as their spherical shape indicate that they probably belong to calcareous micro- and nannoplankton. We therefore conclude that calcareous plankton most probably existed already during the Palaeozoic, but can only be observed under conditions of exceptional preservation.  相似文献   

20.
Poleward shifts in breeding bird distributions in New York State   总被引:1,自引:0,他引:1  
Like other regions of the northern hemisphere, the northeastern United States has experienced a general increase in regional temperatures over the past 20 years. Quantifying the ecological implications of these changing temperatures has been severely constrained by a lack of multispecies distributional data by which to compare long-term changes. We used the New York State Breeding Bird Atlas, a statewide survey of 5332 25 km2 blocks surveyed in 1980–1985 and 2000–2005, to test several predictions that the birds of New York State are responding to climate change. Our objective was to use an information-theoretic approach to analyze changes in three geographic range characteristics, the center of occurrence, range boundaries, and states of occurrence to address several predictions that the birds of New York State are moving polewards and up in elevation. As expected, we found all bird species ( n =129) included in this analysis showed an average northward range shift in their mean latitude of 3.58 km [ Prob ( H a|data)=0.87)]. Past studies have found that northern range boundaries are more likely to be influenced by climatic factors than southern range boundaries. Consequently, we predicted that northward shifts would be more evident in northern as opposed to southern range boundaries. We found, however, that the southern range boundaries of northerly birds moved northward by 11.4 km [ n =43, Prob ( H a|data)=0.92], but this pattern was less evident in northern range boundaries of southerly birds. In addition, we found that bird species demonstrated a general shift downhill in their mean elevation, but demonstrated little change in their elevational boundaries. The repeated pattern of a predicted northward shift in bird ranges in various geographic regions of the world provides compelling evidence that climate change is driving range shifts.  相似文献   

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