180 



only the names of plants which are either quite new on alP 

 the North-Frisian Islands or at least on some of them.. 

 Other botanists, who have travelled in these islands, will 

 most likely have observed several plants^ .which are included 

 in my list, but I believe, I may say, that the plants in my 

 hst are hitherto unknown, at anyrate as far as I know, 

 they have not been introduced into literature before, and 

 of course we can only pay regard to facts made the com- 

 mon property of Science through literature.*) My list is a 

 contribution to a complete flora of the North-Frisian Islands 

 and only supplements the hsts given by Nolte, Schiøtz, 

 Lange, Prahl, Fischer — Benzon and Buchenau. 



While the northern islands Amrum, Føhr, Sylt and 

 Romø are tolerably well investigated, the souhtern, small 

 and low islands, the Halliger are more or less unknown, but 

 what we do know about their vegetation shows us, that its 

 number of species is very small, which also corresponds to 

 the geognostical nature of the islands, and it is not probable, 

 that further investigations of the Halliger will add anything 

 of importance to the list of the vegetation of the North- 

 Frisian-Islands. 



The number of species found upon the North-Frisian 

 Islands is 475 besides 9 doubtful; compared with those of 

 the other islands of the same name, this number is rather 

 considerable: from the East-Frisian Islands we have only 

 about 400 and from the West-Frisian we have about 

 560 species of indigenous plants. Of the 475 plants found 

 upon the North-Frisian Islands 155 are not met with upon 

 the East-Frisian, and again out of these latter 155 species, 

 83 are not found upon the West-Frisian. 



The southern part of Føhr is composed of drift (Dilu- 

 vian-sand), while the northern part is embanked marshland, 

 and here we find small vestiges of sandhills but only to- 

 wards the west. Føhr is guarded by Amrum and Sylt 



*) I am sorry to be unacquainted Avith Dr. Knutlis note on the flora 

 of Sylt. („Humboldt" 1888). 



