102 CORAL AND ATOLLS 



When a name is given to this factor, and it is stated that the 

 corals are a plastic group, it is not quite easy to say what that 

 name should rightly connote ; but although the words when 

 used in their more common sense are not at all apt, I would say 



Fig. 34. 



Millej^ora Colony of the Type named complanata. 



that the corals are an impressionable and responsive class of 

 animals. They are ready to comply with the demands of their 

 environment ; they are, within narrow limits, resourceful and 

 capable of remarkable compromises between the contending 

 forces of inherent growth-form and alterations demanded by 

 changed surroundings. 



Judged as we judge the higher animals, the corals are a 

 class of unstable individuals : we can say definitely that a 

 young elephant will grow up to be an elephant and no other 



