the salt marshes on the Pacific coast of the United States. I 

 think the point he has made is quite a good one, namely, that 

 where you do get the long period of tidal exposure the salinity 

 rises to very considerable heights particularly in the summer 

 months, and under those conditions Salicornia is about the only 

 species that will tolerate the high salinity. On the other hand 

 we find in East Anglia that now that Spartina townsendii has been 

 introduced into the northern coast I have a suspicion that the 

 part formerly played by Salicornia as a primary colonist is go- 

 ing to disappear, and that the Spartina townsendii which comes 

 in at a slightly lower level than Salicornia will extend to such an 

 extent that the Salicornia stage will be almost if not wholly elim- 

 inated. In fact I suspect that possibly on those marshes you may 

 even get the elimination of the Aster stage as well. 



