Armorican Massif)
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Journal of the Czech Geological Society 44/3ñ4(1999) 327 Joachim Barrande and the Paleontology of Paleozoic in Anjou (Armorican Massif) (1 text-figure) HUBERT LARDEUX Universite de Rennes 1, Institut de Geologie, 35042 Rennes Cedex France South-East of the Armorican Massif, the Anjou area, re- At the time when paleontologists from Angers started presents a region distinguished by a special development their research (for example G. Ferronnière, later J. PÈ- (H. Lardeux and P. Cavet, 1994). The various Structural neau to mention only the first two), they used the remar- units that compose it, are considered to be separate, de- cable ìSystème Silurien du centre de la Bohêmeî by Jo- limited by faults of W-NW/S-SE strike, having only few achim Barrande. However, they used also, a precious common features (Fig. 1). collection of Bohemian fossils determined and donated Fossiliferous outcrops are known for a long time and them by Joachim Barrande. One can still admire the per- some of them are famous due to their pecularities, rich- fect calligraphy of the labels of this collection containing ness of fossils or are significant from the view of histo- beautiful samples. ry of science, as they were studied by famous scientists. The inventory list that accompanied the collection of- This is the case for the pelites with Paradoxides of Mid- fers five kinds of information: the label number, the fos- dle Cambrian age from ClÈrÈ-sur-Layon whose facies and sil number, the fossilís name, the locality and the stage. fauna remind us of the classic Skryje outcrops in Bohe- In total, there are 310 ìlabel numbersî virtually corre- mia. It is also the case for the black limestones of La sponding to 310 species and 705 samples. There are thus Meignanne near Angers (LudlowñP¯ÌdolÌ), containing 106 species of trilobites, 70 species of cephalopods, many Bohemian bivalves, or for the Erbray Limestone 30 species of gastropods, 45 species of brachiopods, (PragianñEmsian) brought to fame by the significant 13 species of bivalves, 8 species of graptolites, 12 spe- monograph by Charles Barrois. This occurrence marked- cies of echinoderms. ly reminds the Bohemian KonÏprusy Limestone. The Thanks to Ivo Chlup·Ë (1983 and 1999), it is possi- same is true of the La Grange Limestone, near Chalon- ble to establish the correlation between Barrandeís ìsta- nes, of Emsian age, which shows a typical Bohemian fa- gesî and the formations recognised today. Ivo Chlup·Ëís cies and which is remarcably rich in conodonts, goniati- work also makes it possible to update the name of seve- tes and tentaculites (dacryoconarids). ral classic Bohemian localities. Fig. 1. Paleozoic units of Anjou. A ñ Medio-North-Armorican Do- main; B1 ñ Saint-Julien-de-Vouvantes Unit: Rhenish affinities; B2 ñ Saint- Julien-de-Vouvantes Unit: Bohemian affinities; C ñ Lanvaux ñ Les-ponts- de-CÈ Unit; D ñ Saint-Georges-sur- Loire Unit; E ñ Sillon houiller de la Basse-Loire; F ñ Horst of PouillÈ; G ñ Ancenis Basin; H ñ Metamorphic rocks of Les Mauges Group. 328 Journal of the Czech Geological Society 44/3ñ4(1999) There are too many publications about Paleozoic pa- Chlup·Ë, I. (1983): Stratigraphical position of Barrandeís paleontological leontology of Anjou to list them all here. There is much localities in the Devonian of Central Bohemia ñ »as. Mineral. Geol., to be gained by studying those devoted to general pale- 28, 261ñ276. Praha. ñ (1999): Barrandeís stratigraphic concepts, palaeontological localities ontological studies such as Charles Barrois (1989), Ge- and tradition ñ comparison with the present state. ñ J. Czech Geol. orge FerronniÈre (1920), Joseph PÈneau (1920), Doro- Soc., 44, 1ñ2, 3ñ30. Praha. thÈe Le Maitre (1934), or those devoted to fossils groups Erben, H. K. (1960): Primitive Ammonoidea aus dem Unterdevon such as trilobites: Jean Pillet (1972), brachiopods: Jani- Frankreichs und Deutschlands. ñ Neu. Jb. Geol. Pal‰ont., Abh., 110, ne LíHotellier-Videau (1970), goniatites: Heinrich Erben 128 pp. Ferronnière, G. (1920ñ1922): Le Calcaire de la Grange, prÈs Chalonnes (1960), conodonts: Maurice Lys and Aliette Mauvier (M et L). ñ Bull. Soc. Sci. Natur. de líOuest de la France, 3ème sÈrie, (1965), Pierre Bultynck (1989), tentaculites: Hubert Lar- 6, 1920, 120ñ139; 4ème sÈrie, 1, 1921, 1ñ34; 4ème sÈrie, 2, 1922, deux (1969), Muriel Vidal and al. (1994). 1ñ37. Joachim Barrandeís work has definitely played an im- Lardeux, H. (1969): Les Tentaculites díEurope occidentale et díAfrique portant role in the research done later in Anjou since du Nord. ñ Cah. PalÈont. du C. N. R. S., 238 pp. Lardeux, H. ñ Cavet, P. (1994): Paleozoic of the Ligerian Domain in some geological formations, and in particular those of J. D. Keppie (ed.): Pre-Mesozoic Geology in France and related areas. Devonian age in Ancenis Basin, are remarcably similar Springer Verlag, 152ñ156. in their facies and fauna to the Bohemian units and as- Le Maitre, D. (1934): Etudes sur la faune des calcaires dÈvoniens du semblages. Bassin díAncenis. ñ MÈm. Soc. GÈol. du Nord, 12, 267 pp. We are deeply indebted to Joachim Barrande for pas- LíHotellier-Videau, J. (1970): Rhynchonellida de quelques gisements devoniens (Devonien infÈrieur et Eifelien) du Sud-Est du Massif sing on his collection. The emotion one feels when pic- armoricain. ñ ThÈse 3ème cycle UniversitÈ de Nantes, 220 pp. king up a sample from his collection reminds us of the Lys, M. ñ Mauvier, A. (1965): RÈsultats micropalÈontologiques huge amount of work that went into it and how this fa- (Conodontes) dans le Silurien et le DÈvonien infÈrieur de líAnjou. ñ mous scientist devoted his whole life to Paleozoic pale- MÈm. Bur. Rech. gÈol. min., 33, 1964, 59ñ60. Paris. ontology. PÈneau, J. (1929): Recherches stratigraphiques et palÈontologiques dans le Sud-Est du Massif armoricain (synclinal de Saint-Julien-de- Submitted August 30, 1999 Vouvantes). ñ Bull. Soc. Sci. Natur. de líOuest de la France, 1928, 4Ème sÈrie, 8, 300 pp. Pillet, J. (1973): Les Trilobites du Devonien infÈrieur et moyen du Sud- References Est du Massif Armoricain. ñ MÈm. Soc. Et. scientifiques de líAnjou, 1, 307 pp. Barrois, C. (1889): Faune du Calcaire díErbray. MÈmoires de la SociÈtÈ Vidal, M. ñ Goujet, D. ñ Janvier, Ph. ñ Lardeux, H. (1994): Micro-restes GÈologique du Nord, 3, 348 pp. de VertÈbrÈs du Calcaire de la Grange, Devonien infÈrieur (Emsien) Bultynck, P. (1989): Conodonts from the la Grange Limestone (Emsian), du Sud-Est du Massif Armoricain. ñ Neu. Jb. Geol. Pal‰ont., Abh., Armorican Massif, North-Western France. ñ Cour. Forsch.-Inst. 94, 2ñ3, 321ñ341. Stuttgart. Senckenberg, 117, 173ñ203. Frankfurt a. M..