10 CORALS 



When it has reached a certain size or under certain unknown 

 environmental conditions, it breaks up into four segments, 

 and each of these four segments continues to hve inde- 

 pendently and in time restores the symmetrical shape of 

 its parent. In this case the single individual Diaseris has 

 given rise to four individual Corals of the genus. 



An Alcyonium, a Tubipora, or a Madrepora is an organism 

 consisting of a number of polyps in organic continuity and 

 mutually dependent on one another for their continued 

 existence. 



Here again the Alcyonium or the Tubipora as a whole 

 is, in common language, the individual, and the polyps part 

 or organs of the individual. The conception of individuality 

 has no relation to the structure or function of the parts but 

 to the discontinuity of the living organism as a whole from 

 other living organisms. 



One difficulty, however, in the way of accepting this 

 definition of the word individual is that the corals which 

 are compound or formed of numbers of polyps in organic 

 continuity are frequently called " colonial " corals, and it 

 seems impossible to reconcile the conception of " colony " 

 with that of " individual." 



But the word colony was introduced into the science in 

 error and is really a misnomer. It might be applied to the 

 bees in a hive or to the ants in an ant-nest, for these insects, 

 although congregated together for their mutual advantage, 

 are individually free, and it was due to the error of Reaumur 

 and others of his time, who regarded the calcareous structure 

 of corals as formed in the same way as bees or wasps con- 

 struct their combs, that the expression " coral insects " 

 came into use and the conception of colony formation was 

 introduced. 



As the English-speaking people become accustomed to the 

 use of the word "polyp" the expression " coral insect " may 

 disappear from our language, but it will be more difficult to 

 eradicate the use of the word colony as applied to these 

 animals, because there is no other word in our language 

 which can be readily substituted for it. 



" Zoophyte " is another word which was formerly applied 



