Coral Architects 



continuing ad infinitum. Here again the growth 

 of numbers is not slow. 



Occasionally, in place of spreading in branch- 

 like shapes, they grow in solid rounded masses. 

 Such a sphere-like mass in tropical waters of 

 the Pacific may be twenty feet in diameter — 

 one huge family of united beings, each perhaps 

 under a twentieth of an inch across, and all 

 toofether clothino^ a skeleton common to the 

 entire clan. 



In these cases the tips of the branches or 

 the outer edges of the rounded mass are the 

 young polyps, while the older ones lie lower 

 down or more inward. 



As the tree or ball of coral grows, spreading 

 farther, giving birth to fresh generations of 

 polyps, the old ones die off. So the living 

 and the dead are found in one community, 

 in close touch, on a single branch or a single 

 mound of coral. At the tip of each twig may 

 be the brightly-coloured active jelly, while the 

 stem below is a dead skeleton. On a solid 

 mass of coral, twenty feet in diameter, the 

 whole outside may be alive, down perhaps to 

 a depth of half-an-inch, while the whole inside 

 is lifeless bone. That is how the coral grows. 



Living coral is seldom found at any greater 

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