The Couvinian (a chronostratigraphical unit equivalent to the Uppermost Emsian and to the Eifelian) was made the object of palynological studies concentrating as much on acritarchs as on spores in the eastern flank at the synclinorium of Dinant. The samples are located in a lithological sequence, certain of the units in which are new and defined here for the first time. Their biostratigraphical relations with the type sequence on the south side of the basin were established on the bases of brachiopods. Twenty-three spore species are recorded. Grandispora velata and hystricospores make their first appearance whithin the sequence studied, the first in the Upper Couvinian, the second probably in the Upper Emsian (pre-Couvinian). Their absence permits to date also part of the conglomerate beds which characterize the base of these sequences. Thirty-five species of acritarchs were recognized. Certain are reworked from sediments as ancient as the Cambra-Ordovician, the majority are ubiquitous and already known from the Lower Devonian and even from the Silurian. Some correspond to species already described from the Middle or Upper Devonian. On the basis of the latter, a subdivision of the Couvinian into 4 zones is proposed.