摘要:

Material from Brittany [Bretagne], France, was used for the revision of two trilobite subgenera.Dalmanitina (Eodalmanitina)Henry, 1965 is raised to generic status and maintained in the‘Dalmanitinagroup’ of the Zeliszkellinae;Phacopidella (Prephacopidella)Destombes, 1963, closely related toEophacopsandPhacopidella, is considered an early representative of the Phacopidelli

ISSN:0024-1164    

DOI:10.1111/j.1502-3931.1970.tb01266.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

摘要:

The first certain fossil species of Hirudinea,Epitrachys rugosusEhlers 1869 andPalaeohirudo eichstaettensisn. gen., n. sp., are described from the Upper Jurassic ‘Lithographen‐Schiefer’of Kehlheim and Eichstätt (Bavaria). Hitherto,Epitrachys rugosusEhlers 1868 was assigned to Gephyrea Quatrefages

ISSN:0024-1164    

DOI:10.1111/j.1502-3931.1970.tb01267.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

摘要:

In addition to past errors in correlation and to lack of information, confusion over the lower boundary of the Ashgill Series has been brought about by a tradition of making the boundaries of the graptolitic zones fit a Standard Series based on an overwhelmingly shelly succession. In an attempt to resolve the difficulties, it is here proposed to regard the Pusgillian Stage of Bancroft as the lowest stage of the Ashgill Series. Two new stages, the Cautleyan and the Rawtheyan, are proposed for those sequences recently regarded as Lower and Middle Ashgill respectively, while Bancroft's term Hirnantian is revived as a stage name for the upper part of the Series.

ISSN:0024-1164    

DOI:10.1111/j.1502-3931.1970.tb01268.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

摘要:

During the past 20 years, palaeoecology has established itself as a concept in palaeontology and geology. As in other interdisciplinary sciences, the interchange of methods and terminology between the branches involved has led to changes in the meaning of the terms, and changes or confusion in the corresponding scientific concepts. This calls for stricter adherence to the original definition of the terms in many cases and for their redefinition in others. Starting with a critical review of the scientific and methodological range of palaeoecology, this paper presents a reconsideration of its basic concepts, with proposals concerning the conservation or redefinition of terms and with special regard to terms coined in German literature. It is desirable that similar revisions be undertaken in other language areas in order to attain a stricter, internationalized terminology, preferably substantiated in a dictionary.

ISSN:0024-1164    

DOI:10.1111/j.1502-3931.1970.tb01269.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

摘要:

Multivariate statistical analysis of the anatomical structure of the wood of RecentGinkgo bilobaL. and of fossilGinkgo beckiiScott, Barghoorn,&Prakash revealed significant differences not apparent through general microscopic observation. On the basis of a multiple discriminant analysis by computer of 10 anatomical characters, the living and fossilGinkgowoods were separated into two distinct groups. All Recent wood specimens were classified into a single disjoint group by the computer, and all fossil wood specimens were classified into another without misclassifications when all 10 characteristics were included in the analysis. Three characters—number of pits per millimeter of tracheid length on radial wall, ray height, and tangential diameter of late wood tracheids—accounted for most of the discrimination between the two gro

ISSN:0024-1164    

DOI:10.1111/j.1502-3931.1970.tb01270.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

摘要:

Foraminifera are recorded as feeding chiefly upon bacteria, small diatoms, and nannoplankton in a wide variety of marine environments. Thus their food items are usually below 50 μ and commonly below 25 μ in size. Predators upon Foraminifera range from highly specialized microcarnivores that feed largely on Foraminifera to less selective ones that include Foraminifera in a mixed diet and to generalized feeders that ingest Foraminifera along with much other material.Foraminifera thus form part of a key link in marine food chains, assimilating energy available from minute autotrophs and also retrieving energy available during the final stages of degradation of organic debris. In turn, they support a variety of larger organisms and thus contribute to the diversity and secondary productivity of ecosystem

ISSN:0024-1164    

DOI:10.1111/j.1502-3931.1970.tb01271.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

摘要:

The micro‐ornaments ofNotospiriferspecies consist of a closely spaced array of radially elongate grooves each of which arises in front of a small knob‐like protuberance. In someNotospiriferspecies each groove is prolonged antero‐internally as a cylindrical pit below the surface of the shell. Micro‐ornaments on eastern Australian Permian species ofSubansiriaalso comprise superficial grooves which run forward from small spines. The shells of theseSubansiriaspecies are punctate and each punctum arises within the shell just below the anterior end of one of the superficial grooves. In this case the formation of each punctum seems to have been linked with the formation of a micro‐ornamental groove. The significance of the pits inNotospirifershells is discussed in the light of this possibility. The excellently preserved micro‐ornament of a specimen ofIngelarellais described and

ISSN:0024-1164    

DOI:10.1111/j.1502-3931.1970.tb01272.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

摘要:

A collection of fossil fish from Fossil Lake, Wyoming (Eocene) was compared with samples from three modern natural lakes and an artificial fish pond. All fish were divided into predators or planktivores. The predators all had higher equitabilities than did the planktivores from the same locality. This suggests that the predators are resource limited (food) and that if migration to and from the lakes is not excessive, the equitability of the predatory forms will eventually stabilize at a higher level than that of the planktivorous forms. The paleontological sample follows this pattern, probably from the same causative factors.

ISSN:0024-1164    

DOI:10.1111/j.1502-3931.1970.tb01273.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

ISSN:0024-1164    

DOI:10.1111/j.1502-3931.1970.tb01274.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY