Amphorachitina, Ollachitina, Velatachitina; Trois nouveaux genres de Chitinozoaires de l'Erg Oriental (Algérie-Tunisie)

Description of three new genera of Chitinozoa: Ollachitina n.g., Amphorachitina n.g., Velatachitina n.g.; and of five new species: O. ingens n.g. n.sp., A. conifundus n.g. n.sp., V. veligera n.g. n.sp., V. nebulosa n.g. n.sp., V. copulata n.g. n.sp., which were discovered in drill-cores of oil wells from Cambro-Ordovician deposits of the eastern Erg (Algeria-Tunisia).