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surface relief, subsoil relief (with isohypses every decimeter) give an exact picture of the relationship between the past and present geomor-phological features, and the sedimentation types from tidal fiat and salt marsh landscapes to cover sand landscapes etc. Just as with, for example, Tricarfs mapping of the Senegaldelta, and Dresch’s morphological maps of the Sahara there is simply no other choice than to go, morę or less deeply, into the youngest sediments and their substrate. In fine maps of the glacial lowland geomorphology, published by Galon and Gel-1 e r t, the relationship between substratum, structure and surface forms are successfully compounded (see f.i. Galon 1960, [29]: Morainic hum-mocks transformed by periglacial processes).

As Bulla and Pecsi (1962) have rightly argued the substrate should also be shown in some form in a geomorphological map. This is not only true for sedimentary regions, but also for mountain ranges. One considers here only cuesta- and mesa-landscapes; the totally differ-ing depths of weathering profiles on different parent materiał; parts of watershed regions, where erosion and denudation work morę strongly than at other points (see Hermans 1955). In such cases a morphological map where the relief is shown as an exact isohypsen picture, or according to the morphographic method used by the Belgian investiga-tors, elaborated with a detailed account of the varieties of hard rock, and the thickness and character of the soft rock, is the best method. Maps like those from Jungerius (1 :15,000) of the Moutfort region, and Hermans (1 : 10,000) of the northern part of the Oesling (Luxembourg) are detailed examples of the above-mentioned type. These are pedo-sedimentological maps, but morphological maps too. Also the thickness of a weathering zonę on a plateau, or a region where the soft rock is continually losing materiał by solifluction, and where as a result the weathering profile is only thin, or an eolian sediment on a plateau are a form in the physical-geographical-geomorphological sense and can, no, must, be mapped as such. An exact interpretation of slope development can only be obtained from such maps. Between extreme examples such as Jungerius’ map, where the spotlight falls on substratum and soft rock thickness and Klimaszewskie fine maps of the Polish mountain landscape (1 : 50,000, where the above facts are almost absent) we find the well planned maps from Hungary (Bulla and Pecsi) and Czechoslovakia (De-mek, Panoś et al.). Which road, or roads should we follow?

THE ROAD OR ROADS

Everybody who has had anything to do with mapping knows that one first makes a few proof drawings, and so gradually reaches the finished map. In my opinion the Polish survey is here the most advanced, using a scalę of 1 : 50,000, although there is certainly morę, and above all much morę differentiated morphological mapping than can be seen in Klimaszewskie article (1960, pp. 482-484). But even the best mapping cannot fulfil all ones wishes and all ideals. Therefore it is in my opinion an advantage to make several types of maps of any given area, in each of which one of the five points that I have noted comes into its own. Only then can we accomplish morę satisfactory functional geomorphological mapping and also then special commissions can be better fulfilled.

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2 — Problems