The subdivision of the Netherlands in plantgeographical districts by VAN SOEST (1929) has recently become the subject of a series of investigations by the department for the Netherlands flora of the Rijksherbarium in Leiden (MENNEMA, 1978). This paper deals with one of these investigations, a field study on the border of the Loess and the Chalk district in the South of the Netherlands. In the course of 1976 30 square kilometers were visited and an inventarisation was made of their floristic composition. The data for the distinct square kilometers were subsequently processed by means of the so-called Mennema-methody (MENNEMA, 1973), comparing them in number of species as well as on the basis of „ecologicalgroups” and some critical species. Moreover, to get a general understanding of the floristic composition of the area of investigation, the species were categorised in different types of distribution-patterns, as the square kilometers were studied for their mutual similarity in terms of species-composition. All the different methods lead to the same conclusion: the Chalk district of VAN SOEST (1929) is nothing but a small-scale, winding system of those valleys where limestone can crop up, while the Loess district continues without a change outside the valleys, on the table-land. As such a situation can not be reconciled to a plantgeographical division into two separate districts, a combination of them is proposed under the name Centreurope district, a name originally used by VAN SOEST (1925), before he decided to split up the district.