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c)    the genetic character of landforms (valley terraces, subglacial channels, erosional escarpments, zones of scarp degradation, alluvial cones, dunes, etc.)

d)    the age of landforms (such as Pleistocene landforms produced by the exaration activity of inland ice, lateglacial and postglacial landforms of eolian origin).

The above description of landforms takes into due consideration all the most important features of the relief; as a rule, the morphometric and morphographic features and their character are expressed in the very name of a landform, whereas their age as well as the type of relief-forming process is expressed by its appropriate classification. Herewith are given the categories of age and genetics of the various landforms as distinguished in the Geomorphological Map of the Polish Lowland:

1. Pleistocene landforms produced by the depositional activity of inland ice,

2.    Pleistocene landforms produced by the erosional activity of inland ice,

3.    Pleistocene landforms originated in the zonę of stagnant and dead ice,

4. Pleistocene landforms produced by the depositional activity of glacial meltwaters,

5.    Pleistocene landforms produced by the erosional activity of glacial meltwaters,

6.    Other Pleistocene landforms,

7.    Pleistocene landforms originated under periglacial climate,

8. Lateglacial and postglacial (Holocene) landforms of aeolian origin,

9. Lateglacial and postglacial (Holocene) landforms of erosional and denudational origin,

10.    Postglacial (Holocene) landforms produced by the depositional activity of fluvial waters,

11.    Postglacial (Holocene) landforms produced by the erosional activity of fluvial waters,

12.    Postglacial (Holocene) landforms produced by the activity of lakę and sea waters,

13.    Tectonic forms,

14.    Landforms produced by vegetation,

15.    Anthropogenetic forms.

The list shows that the geomorphological map depicts the dynamics of the relief and of its changing pattern. It differentiates between older groups of landforms developed in various climatic conditions and landforms developing in the modern climate. Thus the geomorphological map expresses the polygenetic evolution of the lowland relief.

Now some of the most important features of the geomorphological map shall be discussed. To start with, this map shows no isohypses (in contradistinction to the geomorphological map of mountains and high-lands). The contours of the region are merely shown by symbols for distinguished landforms; the relative heights are given by numerals indicating altitudes, entered in the map.

Particular attention should here be paid to the altitude scalę applied to scarps in level surfaces, especially to erosional escarpments in the moraine plateau, in outwash plains and in valley terraces. These escarpments are particularly characteristic of the young postglacial landscape.

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