摘要:

Clay and clayey sediments usually have a low content of pollen and consequently some form of enrichment is required before a pollen analysis can be performed. The cotton wool method offers the opportunity of concentrating pollen from samples containing clay in a quick and effective manner. It involves removing the clay fraction from the deflocculated sample by filtering through a cotton wool filter. The residue left on the filter is then removed and concentrated by density separation.

ISSN:0016-786X    

DOI:10.1080/11035898509454646

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

ISSN:0016-786X    

DOI:10.1080/11035898509454647

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

Re-examination of the type material ofTetragraptus phyllograptoidesStrandmark andPseudophyllograptus cor(Strandmark) confirms their unusual morphology and is consistent with the view that they represent morphologic intermediates between reclinedTetragraptusandPseudophyllograptus.Their phylogenetic relationships are discussed and it is suggested that the ‘phyllograptoid’ rhabdosome (i.e. with four scandent stipes) has been independently derived in at least three separate lineages, those leading to Phyllograptus s.s., early ArenigPseudophyllograptusandPseudophyllograptus cor.

ISSN:0016-786X    

DOI:10.1080/11035898509454648

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

ISSN:0016-786X    

DOI:10.1080/11035898509454649

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

ISSN:0016-786X    

DOI:10.1080/11035898509454650

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

ISSN:0016-786X    

DOI:10.1080/11035898509454651

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

This is a scanned image of the original Editorial Board page(s) for this issue

ISSN:0016-786X    

DOI:10.1080/11035898509454635

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor