Our paper explores how tools developed for the formal modelling of individual inflexional systems may be fruitfully applied to the description of inflexion in a dialect continuum or diasystem . We take as our case study the area of central France termed the "Croissant linguistique" (literally, ‘Linguistic Crescent’; Tourtoulon & Bringuier 1876, Brun-Trigaud 1990), usually characterized as a transitional zone between northern Gallo-Romance (Oïl) varieties and southern Gallo-Romance (Occitan) varieties. For each of six survey points within the Croissant area, and a seventh, Occitan, survey point as a comparator, we analyse the inflexional morphology of the verb, using two principal formalizations: Paradigm Function Morphology (Stump 2001, 2016, Stump & Finkel 2013, Bonami & Stump 2016) and stem spaces (Bonami & Boyé 2002, 2003, 2014, Boyé 2011). By these means, we obtain schemas highlighting the key principles of paradigm organization in each individual variety. Comparison of the schemas reveals structural continuities and discontinuities within the Croissant dialect continuum itself, and between the Croissant dialect continuum and neighbouring varieties.