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PACIFIC SCIENCE, Vol. IV, October, 1950 
The boundaries of this community cannot be since Melaraphe is able to move within a 
delimited precisely in terms of tide levels relatively restricted area to a more favorable 
PERCENTAGE EXPOSURE 
Fig. 7. The vertical range of 25 inter-tidal species (* found to be Enteromorpha procera f. minuta) 
in relation to annual percentage exposure and submergence. (The limits are averaged from data 
obtained in the four traverses.) 
