The GSSP at La Serre in the Montagne Noire, southern France, is far from being an ideal GSSP -
that would be an ideal representation of time by rock (Paproth et al., 1991). lt seems, however, to be a
GSSP that excludes misinterpretations and ambiguity. As the GSSP lacks some important stratigraphic
guides, as cephalopodes (to a large extent), spores and ash layers for radiometric dating, the appropriate
Working Group was induced to support the GSSP by the Auxiliary 8tratotype Sections of Hasselbachtal
and Nanbiancun.  As has been demonstrated in the proposition of the GSSP to the International Stratigra-
phical Commission, these two meticulously described sections confirm and guarantee without any reaso-
nable doubt the right position of the Devonian-Carboniferous boundary at the base of Bed 89 in La
Serre (Becker et al., 1984; Flajs & Feist, 1988; Yu, 1988).