294 



Berings Strait, shores of the Arctic coast of America, Hud- 

 son Strait, West Greenland from 70° to 81° 40' Latitude, 

 East Greenland at 70° Latitude, Spitzbergen, Novaya Zemlya, 

 Waigatsch and the Taimyr-peninsula. 



III. 

 Draha. 



At the request of Prof. E. Warming I have revised 

 the Cruciferce of the Arctic Herbarium of the Botanical 

 Museum at Copenhagen. In order to get clear views upon 

 the numerous species of Draha ^ which have been quoted 

 from Arctic regions, I have been obliged to submit them to 

 a very close study. I have had the greatest help from the 

 excellent revision of the genus Draha by Watson in Asa 

 Gray: Synoptical Flora of North-America. Besides the rich 

 material of the Botanical Museum at Copenhagen, especially 

 from Greenland, I have had the opportunity of studying 

 several species from the Botanical Museums at Stockholm 

 and St. Petersborg ; and visiting London , I saw a great 

 number in the British Museum and the Kew Herbarium. As 

 I suppose, that my observations may prove of use for a 

 future revision of the whole genus, I shall venture to present 

 them here. 



Draha glacialis Adams. 



This plant is referred to the Section „ Chrysodraba" 

 by Ledebour in his Flora Rossica and to the Section „Ai- 

 zopsis^ by Watson, but by many authors it is taken for a 

 variety of Draha alpina. Unfortunately I have not seen any 

 authentic specimen of this species from Asia, but I have seen 

 specimens from America determined by W. Hooker, which 

 closely agree with the description given by De CandoUe 

 (Fig. 4). According to these specimens, Watson has put the 

 plant in the right place. From all other Arctic species of 



