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the Kara-Tajmyr block (Severnaya Zemlya), and even with the northern part of Siberia (Central Tajmyr and Noril'sk region).
All three members of the French group also attended the Jurmala meeting (Riga, Latvia: 4th BSC and IGCP 406 annual meeting) for both the scientific sessions and the Devonian field excursion, supported in part by the French IGCP Committee.
A. Blieck (Lille) collaborated in Vilnius in October, 1999, with V. Karatajute-Talimaa. The main results of this study (which began in 1997) are as follows (as reported by A. Blieck):
1) systematic and biostratigraphic study of Devonian heterostracan pteraspidomorphs of October Revolution Island, Severnaya Zemlya (SZ), Russia, occur in the Severnaya Zemlya, Pod'emnaya, and Spokojnaya Fms (Lochkovian-Pragian), but are absent from the overlying Rusanov and Al'banov Fms (Emsian); 2) The major higher taxa of heterostracans have been collected, i.e., Tesseraspidiformes, Corvaspidiformes, Traquairaspidiformes, Cyathaspidiformes, Amphiaspidiformes, and Pteraspidiformes; several new species have been found, which correspond to the following genera: Anglaspis, Ctenaspis, Miltaspis?, perhaps Corvaspis, and some Pteraspidiformes;
3) A detailed biostratigraphical scale at the specific level is in progress for the five studied localities: Matusevich River, Ushakov River, Spokojnaya River, Pod'emnaya River, and Sovetskaya Bay; this will lead to locality-by- locality detailed correlation, a regional synthetic biostratigraphical scale, and eventually to correlations with Spitsbergen and other circum-Arctic areas;
4) The Early Devonian heterostracan assemblages of SZ are mostly similar to the Spitsbergen ones, but have several taxa in common (at least at the generic level) with the Canadian Arctic Archipelago (now part of Nunavut) and the Mackenzie District of NWT, Canada;
5) This confirms some palaeobiogeographical reconstructions for early Devonian times, in which the Kara-Taimyr block (plate), which bears SZ, is located near the "northern" edge of the ORSC, and close to the Barentsia plate, which bears Spitsbergen. However, the SZ sequence also yields amphiaspid heterostracans which are known only from Central Taimyr (Tareya river section for instance) and NW Siberia (Noril'sk area for instance). This suggests rather close palaeobiogeographical relationships between the Siberian palaeocontinent and the ORSC + Barentsia + Kara-Taimyr complex [+ Chukotka];
6) A new Protopteraspididae (gen. et sp. nov.) is also known from the Mid-Devonian (Eifelian) Vstrechnaya Fm of October Revolution Island; it is the stratigraphically youngest pteraspid from the Old World (but younger ones, Givetian in age, are being published from the USA by D. Elliott et al.) [other heterostracans come from the Middle and Upper Devonian (Eifelian to Frasnian) of the SZ sequence; they consist of psammosteids and are under study by E. Mark-Kurik (Estonia)].
P.-Y. Gagnier (Paris), as a complement to morpho-anatomical work on the acanthodian fishes from the Lower Devonian of the Mackenzie mountains in the Canadian Northwest Territories, began description of Silurian- Devonian microremains of acanthodians from Baillie Hamilton and Cornwallis islands in the Canadian Arctic. The aim is correlation with equivalent sections of the Boreal and Arctic areas of Europe and Asia. D. Goujet (Paris) reports the following results:
1) completion for publication of the revision of the Spitsbergen Arthrodire Arctaspis gigantea. 2) preparation of the material of Amaltheolepis(Thelodonti) from the Wood Bay Formation of Spitsbergen, to be described in collaboration with Henning Blom (Sweden).
3) during a three month visit of Dr. Gavin Young (Australia) in Paris, collaboration on the comparison of the Spitsbergen phlyctaeniid and actinolepid placoderm faunas with the Lower Devonian forms of Eastern Australia (Craven's Peak and Mulga Downs).
4) editorial work on the special volume on the Silurian and Devonian of Severnaya Zemlya to be published in the year 2000 by Geodiversitas,Paris. Some 13 papers for this volume have now successfully passed the refereeing stage (see list of publications for complete details).
5) attendance, presentations, and abstracts at two meetings: Major Events in Early Vertebrate Evolution: Palaeontology, Phylogeny and Development: London 8-9 April 1999; IGCP 406 Annual Meeting: Riga (Jurmala) 37-30 September 1999.
Germany:
M. Otto, G. Arratia, and H.-P. Schultze all attended the Jurmala (Riga) meeting. G. Arratia organized a symposium on the evolution of the heads of fishes at the Society of Vertebrate Paleontology meetings in Denver, U.S.A.