i6o W. S. Cooper 



three companion species. It is found on the coasts of arctic 

 Russia and Norway, in the British Isles, in Denmark, Spitz- 

 bergen, Jan Meyen Island, Iceland, and Greenland. On the 

 Adantic coast of North America it ranges southward to Nan- 

 tucket Island. It is found on the shores of Hudson Bay, in the 

 Canadian Arctic Archipelago, on all coasts of Alaska, the Aleu- 

 tian Islands, eastern Siberia, Kamchatka, and southward in 

 Korea and Japan. There seem to be no records of its occurrence 

 on the arctic coast of Siberia, except in the vicinity of Bering 

 Strait. The Asiatic form has been distinguished as subsp. asiatica 

 Takedo (Hulten, 1927-30). MacBride (1916) gives this form 

 specific rank. 



The genus Mertensia is found in the north temperate regions 

 of the Old and the New World (Giirke, 1897). Extensive devel- 

 opment of the genus in the mountain regions of western North 

 America may be a relatively recent event in its history. There 

 seems to be no genetic connection between this group and M. 

 maritima. 



Franseria bipinnatifida Nutt. (fig. 6h) and F. chamissonis 

 Less. (fig. 6/), ecological equivalents, are conspicuous members 

 of the foredune community. They commonly produce low 

 mounds, but are not particularly efficient in this because they 

 lack capacity for upward elongation. They are far more impor- 

 tant as secondary invaders of hillocks already established by 

 other species. 



Of the two, F. bipinnatifida has the more extended range. The 

 northernmost certain locality is Ucleulet, Vancouver Island. It 

 has been reported from Nootka Sound, Vancouver Island (Ma- 

 coun, 1883-90), and from Queen Charlotte Islands (Macoun, 

 loc. cit., on authority of Dawson), but these records need veri- 

 fication. The southernmost locaUties in North America are 



