146 W. S. Cooper 



Poa macrantha is related to P. eminens Presl, a coastal species 

 of northeastern Asia and arctic America (Hulten, 1927-30), and 

 to P. lahradorica Steudel of the coast of Labrador. It may perhaps 

 have become differentiated in the course of migration of sub- 

 arctic stock southward along the Pacific coast. Poa confinis and 

 P. douglasii are probably close relatives, but their affinities with 

 other species are not clear. It is at least a reasonable hypothesis 

 that they originated in the same way. 



Ely m us arenarius L. var. villosus E. Mey. (figs. 2fl, 3^) is the 

 most characteristic and conspicuous strand-plant on the shores 

 of the northern Pacific ocean. In southern Alaska it forms a belt 

 of nearly pure growth at the top of the beach. South of Puget 

 Sound, it inhabits the foredune zone and forms small hillocks. 

 Southward it becomes progressively less abundant. Its southern 

 limit in 1927 was very definitely fixed at the mouth of the Salinas 

 River on Monterey Bay. 



This species, in its two principal varieties, is probably circum- 

 polar in distribution. The typical form inhabits the northwestern 

 coasts of Europe — the British Isles, the southern Baltic, Norway, 

 Iceland. The variety villosus E. Mey. [subsp. mollis (Trin.) 

 Hulten] occurs on the coasts of northeastern America south- 

 ward to Cape Cod (St. John, 1915), Hudson Bay, the Arctic 

 Archipelago, the entire coast of Alaska, and southward on the 

 Pacific coast of America as outlined above. It continues along 

 the Aleutian Islands to the coasts of eastern Siberia, Kamchatka, 

 Manchuria, and Japan. Reported occurrences at the mouth of 

 the Lena River and the Taimyr Peninsula indicate that its range 

 is probably fairly continuous along the arctic coast of Siberia, 

 thus connecting with that of the typical form. The species occurs 

 also on the shores of large interior lakes — Ladoga and Onega in 

 Russia; Superior, Michigan, Athabaska, and probably others in 



