CHAPTER VIII 



THE GROWTH OF THE CORAL COLONY 



The coral embryo that has settled down, and started its 

 processes of division and budding, becomes the father of the 

 colony, and the rate of growth of this colony is a matter of 

 some importance. Since coral colonies may be regarded as 

 the bricks of which the whole edifice of an atoll is composed, 

 it is of interest to know how fast these bricks are made 

 beneath the sea that will one day tear them from their beds 

 and heave them up to form dry land. 



As a number of observations were made during the fifteen 

 months of residence on the atoll, and some care was taken in 

 recording these observations, and in eliminating errors, it will 

 be as well to give in brief the actual figures arrived at. All 

 the specimens measured were normal colonies growing in their 

 natural habitat, and care was taken that the processes of 

 measurement did not act harmfully upon the colony ; in no 

 case was a coral moved to its site of observation from a 

 previous habitat. Branching forms were recorded by carefully 

 measuring the branches at times when wind and tide permitted 

 of accuracy, and by fixing a little band of copper round the 

 branches at a distance of 10 centimetres from the distal 

 extremity. Numerous branches, averaging 20 centimetres in 

 length, were taken on many different colonies, and the 

 distance of the band of copper from the tip of the branch was 

 measured from time to time. 



It is only fair to say that the results were extremely 

 variable : branches would grow fast, and then pause ; and some 

 that for weeks showed no activity would suddenly enter on a 

 period of unusually rapid growth. 



The reason for these fits and starts of growth is not easy 



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