Strand and Dune Flora of the Pacific Coast 177 



genus that is typically northern. The same is true of Lathyrus 

 japonicus, which, although found in South America, falls more 

 naturally into group i. Carpobrotus chilensis, on the contrary, 

 belongs to a group centering in South Africa which has spread 

 eastward and westward, finally reaching our territory by way of 

 South America. It is the only species that has certainly entered 

 from that direction. 



5. Species of general distribution upon subtropical coasts. 

 Convolvulus soldanella, the most widely distributed of all our 



strand species, is, judging from the general range of the family, 

 of subtropical origin. 



6. Endemics, 



The species of this group, confined to the area under discus- 

 sion, show various extraregional affinities. The following eight 

 species are quite definitely derived from stock which has long 

 inhabited the more or less arid parts of western America: 



Atriplex leucophylla Lupinus littoralis 



Abronia latifolia Oenothera cheiranthifolia 



Abronia maritima Franseria bipinnatifida 



Abronia umbellata Franseria chamissonis 



The remaining five represent genera mainly north temperate 

 in distribution, present in western America but not characteristic 

 of the adjoining arid regions: 



Poa confinis Polygonum paronychia 



Poa douglasii Lathyrus littoralis 



Poa macrantha 



From the analysis here presented, the following generaliza- 

 tions concerning the origins of the flora may be made. 

 Fourteen species of eleven genera, some endemic, some with 



