332 



also pay attention to the opinion, that we should havc 

 got to do here with a loess-like material. Has not 

 V. Cappelle in 1900 defended the theory, that loess 

 is a deposit of rivers, and argued, that there is in our 

 country a distinct connection between the distribution of 

 the loess and the course of the IJsel, Rhine and Meuse? 

 Now I know very well, that others consider loess to be 

 a deposit of the wind, but I should like to ask as non- 

 expert on this subject, whether not here also truth lies 

 midway. Here again the botanist knows, that at présent 

 still such things as deposits made by the wind, being 

 washed away by the water, happen in the Alps. The 

 wellknown "Schneetâlchenflora" is e. g. a resuit of it. 

 Would it not be possible, that what we see take place 

 at présent has also happened in the past and that it is 

 of importance to understand the loess-deposits? Still an- 

 other important point mentioned by Prof. Tan si e y 

 was, that the "Breckland-area" contains a séries of further 

 species, which are not found elsewhere in England or 

 which are nearly confined to it. At my request, the names 

 were kindly given to me and in this way I hâve had the 

 opportunity to work in inverse direction, which has given 

 me additional évidence. 



Strictly confined to the "Breckland-sands" are accor- 

 ding to Prof. Tansley still the folio wing plants: Medi- 

 cago falcata L.,Yeronica verna L.,Veronica spicata L., Carex 

 ericetorum Poli and Ornithogalum umbellatum L. The 

 Dutch botanist recognizes the first of thèse species at once as 

 a river-plant. In our country it only occurs along the big 

 rivers Meuse, Waal. Rhine, IJsel and also along the old 

 Rhine-bed o'f Van Eeden. In Belgium it is very rare 

 in the south-east corner, rare within the range of the 

 Meuse and in the central part, but in the latter, according 

 to Crépin, perhaps only an alien. It certainly is there- 

 fore of importance to our purpose. In Germany it is 



