Abstract
Fifty-six graptolite species and subspecies are described from the Silurian sediments of Washington Land and Hall Land, western North Greenland. The graptolite faunas indicate the following ages and zones: Middle Llandovery, the argenteus and convolutus Zones; Upper Llandovery, the turriculatus and spiralis Zones; probably the Llandovery to Wenlock transition; Lower Wenlock, the riccartonensis Zone; Uppermost Wenlock (?) and Lower Ludlow. The bulk of the graptolite species are well known, but some new minor morphological grades are recognised. Four new species and one new subspecies Pseudoclimacograptus (Clinoclimacograptus)? washingtoni, Plectograptus? intermedius, Monograptus kochi, Monograptus teicherti,– and Monograptus bjerringus schucherti – are erected. P. (C.)? washingtoni and P.? intermedius possess morphological characters which are referable to more than one previously described subgenus and genus. The retiolitid fills a gap in the known record of the retiolitids.
Highlights
Silurian graptolites of Middle Llandovery to Lower Ludlow Age are described from the folIowing localities in Washington land, western North Greenland: Kap Independence, Graptolitnæs, 'Kap Schuchert' (2 km south ofKap Schuchert), Kap Godfred Hansen and Kap Lucie Marie
In addition Berry et al (1974) reported a few graptolites from the margin of the North Greenland fold belt of western Hall Land to be of Pridoli and earliest Devonian Age
B. bohemicus apparently has a shorter range in Arctic Canada than Europe (Thorsteinsson, 1958; Jackson & Lenz, 1962) and may indicate a level around the scanicus-nilssoni to bohemicus Zones in the Lower Ludlow
Summary
Silurian graptolites of Middle Llandovery to Lower Ludlow Age are described from the folIowing localities in Washington land, western North Greenland (fig. 1): Kap Independence, Graptolitnæs, 'Kap Schuchert' (2 km south ofKap Schuchert), Kap Godfred Hansen and Kap Lucie Marie. Silurian graptolites of Middle Llandovery to Lower Ludlow Age are described from the folIowing localities in Washington land, western North Greenland A small collection of Silurian graptolites collected by Lauge Koch during an expedition to Washington Land between 1916 and 1918 is described. In addition the graptolite material, collected by Lauge Koch, from Kap Schuchert and listed and figured in Poulsen (1934), has been reexamined. In addition Berry et al (1974) reported a few graptolites from the margin of the North Greenland fold belt of western Hall Land to be of Pridoli and earliest Devonian Age. H. A large portion of the graptolites are badly preserved as incomplete carbon films with indistinct structures For this reason about ten species or subspecies, which cannot be safely assigned to known species, are not described as new. Thecal structures are generally obscure and add no additional information to the aiready known detailed thecal morphology
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