186 



towered above extensive, low heath-flats and swampy moor- 

 lands, by which it was connected with the mainland on 

 the north and east. We may also look upon Romø and 

 Fanø as remains of those heats-flats. The vegetation of 

 these islands carries on an unceasing struggle * with the- 

 sand, a struggle in which many plants succumb, never- 

 theless the vegetation exactly corresponds with the vegeta- 

 tion on the low and flat heathy- country to the north on 

 the inner side of the sandhills between the bay of Ho and 

 the firth of Ringkjøbing. Amongst the most characteristic 

 plants of these localities are Car ex triner vis, Heleocharis^ 

 midticauUs, Malaxis paludosa and Fyrola minor. 



Among the vegetation-formations of the North-Frisian 

 Islands I have included the woodformation, which is but 

 scanty. I do not think Buchenau is right in saying in his 

 interesting paper on the flora of the North-Frisian Islands, 

 that there is an essential difference between those and the 

 East-Frisian, the latter possessing remains of a wood-vege- 

 tation the former showing no sign of it, so that, only waste 

 heath- and bog-lands were to be found here when the 

 sandhills were formed and the lower tracts were overflowed 

 by the sea. There is certainly a difference here but it is 

 the same which we found in considering the other vegeta- 

 tion-formations, namely the evident connection of the North- 

 Frisian Islands with West-Jutland. That the land has once- 

 been wooded is destinctly proved by the stationary stumps 

 of trees on the shoals („Vaderne") between the islands. 

 Besides those I found some apparently old buches of Betula 

 odorata var. puhescens on sandhill-flats south of the hghthouse 

 on Amrum ; to judge from their way of growing, they were 

 indigenous; wlietlier this was the case with Popidus tremula 

 which I also found on the sandhill-flats and valleys on the 

 southern part of Amrum I cannot say. In addition to 

 these two woody plants the North-Frisian Islands have 

 some wood-herbs although these are scarce, some of which 

 are wood-plants in so far that they are not able to sepa- 

 rate from the wood and enter a different vegetation as in 



