bo 
No 
Postelsia 
Bromus pacificus Tanacetum huronense 
Ammodenia major Aster foliaceus 
Nabalus alatus Anaphalis subal pina 
Sonchus as per 
In very severe storms it may happen that 
there is great addition to, or a considerable 
shifting of the driftwood deposit and when this 
occurs, a readjustment of the society naturally 
ensues. New conditions arise and a response to 
these will show itself in new arrangements. The 
beach at the head of San Juan Harbor is a com- 
paratively wide sandy waste. Its slope is very 
eradual and during high seas the waves wash 
nearly up to the forest edge. Vegetation is 
therefore extremely scanty and is confined to a 
narrow strip of the back beach where the most 
typical plants are the following xerophytes:- 
Atra caryophylla Carex macroce phala 
Deschampsia caespitosa Artemisia suksdorfii 
b. Small inlet -beach. 
Upon the small sand beaches at the mouths 
of ravines it is perhaps more difficult to — dif- 
ferentiate between the front and back regions 
