摘要:

The Permian ammonoid family Cyclolobidae Zittel is essentially of Middle Permian age, and most species ranged over the paleotropical into temperate regions, and lived for no more than one to three stages. The time ranges of the three principal genera,Waagenoceras, TimoritesandCyclolobusoverlap to some degree, so correlation must be based on species rather than genera.Cyclolobusevolved fromGodthaabites, and both inhabited temperate paleolatitudes on the whole.Cyclolobusinhabited a small region, now dispersed around the rim of the Indian Ocean. TheWaagenoceras ‐ Timoriteslineage, contemporaneous with theGodthaabites‐Cyclolobussuite, inhabited paleotropical latitudes, andTimorites is foundaround the rim of the Pacific Ocean. Such genera, restricted in longitudinal as well as latitudinal distribution, are important in constructing pre‐drift distribution of plates.The Kalabarghian and Chhidruan faunas of the Salt Range are identical with the Capitan Stage (sensu lato) of Texas. Younger Permian rocks and faunas are subdivided into the Kathwai fauna, the Baisalian, Vedian, Ogbinan faunas, followed by the Makarewan Stage of New Ze

ISSN:0024-1164    

DOI:10.1111/j.1502-3931.1972.tb00857.x

出版商:Blackwell Publishing Ltd    

年代:1972

数据来源: WILEY

摘要:

The controversial upper age limit of the East Coast Gondwanas is discussed. A reassessment of the evidence furnished by animal and plant fossils is made in view of recent findings. Whereas the flora points towards a Jurassic age, the ammonites and other invertebrate megafossils indicate a Neocomian age. The microfossils support the concept of an Early Cretaceous age. The conflicting evidence of flora and fauna and the probable reliability of each is discussed. Although there is some doubt about the correctness of the floral testimony, the reliability of faunal evidence seems established, and an Aptian or Albian age is favoured as the upper age limit of the East Coast Gondwanas.

ISSN:0024-1164    

DOI:10.1111/j.1502-3931.1972.tb00858.x

出版商:Blackwell Publishing Ltd    

年代:1972

数据来源: WILEY

摘要:

Additional and corrected information is given regarding the stratigraphy and palaeoecology of the thelodont‐bearing sequence on Prince of Wales Island. The thelodont fauna is not older than latest Wenlockia

ISSN:0024-1164    

DOI:10.1111/j.1502-3931.1972.tb00859.x

出版商:Blackwell Publishing Ltd    

年代:1972

数据来源: WILEY

摘要:

International Subcommission on Stratigraphic Classification [Report No. 7a; editor H. D. Hedberg]: Introduction to an International Guide to Stratigraphic Classification, Terminology, and Usage.Lethaia, Vol 5, pp. 283–295. Oslo, July 15th, 1972.The International Subcommission on Stratigraphic Classification (ISSC), a subcommission of the IUGS Commission on Stratigraphy, has been working for the last 15–20 years towards the preparation of an International Guide to Stratigraphic Classification, Terminology, and Usage. The purpose of the Guide is to promote international agreement on principles of stratigraphic classification and to establish internationally acceptable stratigraphic terminology and rules of stratigraphic procedure. The Introduction explains the background of its preparat

ISSN:0024-1164    

DOI:10.1111/j.1502-3931.1972.tb00860.x

出版商:Blackwell Publishing Ltd    

年代:1972

数据来源: WILEY

摘要:

International Sub commission on Stratigraphic Classification [Report No. 7b; editor H. D. Hedberg]: Summary of an International Guide to Stratigraphic Classification, Terminology, and Usage.Lethaia, Vol. 5, pp. 297–323. Oslo, July 15th, 1972.Six published reports (and some 40 circulars) of the International Sub commission on Stratigraphic Classification (ISSC) constitute the principal bases for the initial edition of an International Guide to Stratigraphic Classification, Terminology, and Usage. The published reports on Lithostratigraphic Units, Biostratigraphic Units, Chronostratigraphic Units, and Stratotypes are advance chapters of the Guide. The following Summary, which with the preceding Introduction will form the first chapter of the completed Guide, provides a concise and condensed statement of principles, definitions, and proposed rules, which are elaborated in more detail in the published reports and individual chapters of the Guid

ISSN:0024-1164    

DOI:10.1111/j.1502-3931.1972.tb00861.x

出版商:Blackwell Publishing Ltd    

年代:1972

数据来源: WILEY

摘要:

Shingled divaricate ribs occurring in several unrelated groups of pelecypods are highly functional structures related to specific burrowing processes. However, their obliqueness and ambivalence, seemingly the most aberrant features, are shared by a variety of colour, mineralization, and groove patterns both in the functional and non‐functional field. Their basic form is assumed to be less controlled by adaptation and phylogeny than by a common principle of shell growth, the nature of which has still to be found ou

ISSN:0024-1164    

DOI:10.1111/j.1502-3931.1972.tb00862.x

出版商:Blackwell Publishing Ltd    

年代:1972

数据来源: WILEY

摘要:

Jessen, H. L.: Schultergürtel und Pectoralflosse hci Actinopterygiern. [Shoulder girdle and pectoral fin in actinopterygians.]Fossils and Strata, Number 1, pp. 1–101, Pls. 1–25. Oslo, 5th May 1972.The anatomy of the shoulder girdle and pectoral fin is investigated in adults and larvae ofAsperser, Amia, Lepisosteus, Elops, Salmo, andPolypterus. In comparison with similar structures in other gnathostomian fishes these studies yielded certain conclusions as concerns the interrelationships of the recent actinopterygian groups and the affinities of the hrachiopterygians, the latter by this evidence belonging to an evolutionary line of their own. With regard to actinopterygian phylogeny, a comparison with the shoulder girdle and pectoral fin in fossil forms, includingChondrosteus, Moythomoasia, Palaeoniscus, Pteronisculus, Pachycormus, Catarus, Hypsocormus, andBirzeria, shows that teleosteans presumably are closer to chondrosteans than holosteans, and that holosteans seem to have branched off comparatively early from the actinopterygian

ISSN:0024-1164    

DOI:10.1111/j.1502-3931.1972.tb00863.x

出版商:Blackwell Publishing Ltd    

年代:1972

数据来源: WILEY

ISSN:0024-1164    

DOI:10.1111/j.1502-3931.1972.tb00856.x

出版商:Blackwell Publishing Ltd    

年代:1972

数据来源: WILEY