摘要:

Krassilov, Valentin 1978 04 IS: Organic evolution and natural stratigraphical classifcation.Typological stratigraphy persisted up to the early 1940's. when it gave way to gradualistic concepts. Because world‐wide periodicity of evolutionary events and their functional relations to crustal disturbances were denied, it was decided to define geological time divisions by a set of time‐planes marked by agreed reference points. Actually, evolution is discontinuous at the molecular, population, species and community levels. Evolution of the whole biosphere depends on periodicity of tectonic and climatic events which add to general environmental instability and alter adaptive strategies. The perception of geological time is derived from the succession of unique litho‐ and biosphere events which Serve as a base of natural stratigraphical classification. Correlation is based on the parallelism of cliseres and chronoclines. Their homotaxial members are recognized as coenozones and phenozones. Standard stratigraphical boundaries are materialized in local boundaries defined by historical events of high ‘confidence level’. Nominotypes designated for nomenclatural procedures need not coincide with the boundary reference points; otherwise they would hamper further development of stratigraphical class

ISSN:0024-1164    

DOI:10.1111/j.1502-3931.1978.tb01292.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

ISSN:0024-1164    

DOI:10.1111/j.1502-3931.1978.tb01293.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

Linsley, Robert M., Yochelson, Ellis, L.&Rohr, David M. 1978 04 15: A reinterpretation of the mode of life of some Paleozoic frilled gastropodsMost modem gastropods crawl, and support their shells up off the substrate. However. five different groupings of snails predominantly rest their shell upon the substrate. One group,Xenophora‐like in habit, lives with the base of the shell propped above the substrate by a frill or spines. Re‐examination of the SilurianEuomphalopterusshows that the broad frill is not a selenizone as it has been most frequently interpreted. The broad frill may have served the function of propping the aperture above the substrate. All members of the Euomphalopteridae are reassigned. A review of Paleozoic gastropods suggests that this propping mode of life was adopted more than once by unrelated gastrop

ISSN:0024-1164    

DOI:10.1111/j.1502-3931.1978.tb01294.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

Berg‐Madsen, Vivianne&Peel, John S. 1978 04 IS: Middle Cambrian monoplacophorans from Bornholm and Australia, and the systematic position of the bellerophontiform molluscsMinute Middle Cambrian monoplacophorans originally reported from Australia are redescribed on the basis of material from the Kalby Clay of Bornholm. A recent classification ofBellerophon. Sinuitesand related genera as monoplacophorans is discussed and rejected. Members of the group are returned to the Gastropoda on account of their similarity in ornament, musculature and inferred water circulation patterns, with contemporary fossil helically coiled gastropods. Water circulation patterns are deduced inProtowenella flemingiand support the assignment to the Monoplacophora.Kulhyella poulsenin.gen. n.sp. is describe

ISSN:0024-1164    

DOI:10.1111/j.1502-3931.1978.tb01295.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

ISSN:0024-1164    

DOI:10.1111/j.1502-3931.1978.tb01296.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

Turek, Vojtach 1978 04 15: Biological and stratigraphical significance of the Silurian nautiloidCircular or elliptical structures described as the genusAptychopsisBarrande 1872 (and mostly referred to the Crustacea) represent the opercula of a specialized group of orthoceratids. Their morphology bears a considerable resemblance to the structure of the lower jaws (aptychi) of some Mesozoic ammonoids, particularly of the genusPhysodoceras. Because of its size and structure, however,Aptychopsiscannot have functioned as a jaw apparatus. Observation of an operculuminsirusupports this assumption as regards its functional and systematic position. The classification of the genusAptychopsisas given by Jones and Woodward (1872–1893) is purely typological and hardly applicable in palaeobiology. Continuous gradations exist between the various morphological types. The lack of systematically distinctive features explains the unsuitability ofAptychopsisfor biostratigraphical use. Aptychopsids occur in the Silurian of Central Bohemia between theSpirograprus turriculatusZone and theNeodiversograptus nilssoniZone, inclusive, with maximum frequency in the uppermost Wenlockia

ISSN:0024-1164    

DOI:10.1111/j.1502-3931.1978.tb01297.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

Schopf, James M. 1978 04 15: Foerstia and recent interpretations of early, vascular land plantsFoerstiashould be regarded as a marine fucoid, contrary to the recent interpretation of Gray and Boucot who relate these fossils to land plants. Although the megaspore coats are resistant and may be waxy, the thallus lacks cuticle and it has internal filamentous tissue likeFucusand other fucoidal algae. The megaspores, borne in fucoidal conceptacles, are unusual and may be forerunners of the more reduced oocytes that occur in modern Fucales. Detailed illustrations are provided. There is no evidence that these plants have ever been anything but marine. Likewise, tubular microfossils that show internal thickenings and occur in Ordovician and Silurian marine deposits should not be designated ‘tracheid‐like’, as done by Gray and Boucot, because it is unlikely they represent land plants or function in conduction. They show a surprisingly consistent association with Chitinozoa. They illustrate the adage that structures identified simply by their form may be of diverse origin. NeitherFoersrianor the annulate tubules are relevant to the origin of temestrial veget

ISSN:0024-1164    

DOI:10.1111/j.1502-3931.1978.tb01298.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

ISSN:0024-1164    

DOI:10.1111/j.1502-3931.1978.tb01299.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

A Haugh, Bruce N. 1978 04 IS: Biodynamic and phyletic paradigms for sensory organs in camerate crinoidsFunctional analysis of thecal pores and associated fixed pinnules of camerate crinoids reveals that they may have been organized into an integrated current‐sensing biologic system. Paleobiologic, biodynamic, and geometric evidence reveals a potential for sensing the direction and intensity of horizontal water currents. An ahistoric paradigm predicts that the inferred sensory organs could have elicited several alternative feeding postures and a survival posture in response to current intensity. Possession of long anal tubes is judged to be related to the sensory function. By virtue of these adaptations certain camerates may have been discriminatory rheophilic feeders in complex fdter feeding communities. An historically founded phyletic paradigm suggests that a functional change in thecal pores and pinnules occurred in the Early Mississippian as an evolutionary concourse in several independent lineages. This specialized sensory innovation may have signifcantly contributed to the ‘flowering’ of camerates in rheic carbonate environments as well as their demise in terrigenous clastic environments. Phyletic paradigms illustrate the advantage of functional analysis of fossil structures at several points in time and especially at the acme of development when structure and function are commonly most clearly deli

ISSN:0024-1164    

DOI:10.1111/j.1502-3931.1978.tb01300.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

ISSN:0024-1164    

DOI:10.1111/j.1502-3931.1978.tb01301.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY