DEATH-PROCESSES OF CORAL COLONY 133 



reasons for believing that there is only one species of 

 Millepora" {P. Z. S., 1898, April, p. 256). 



Previous to the writing of this paper he had come to the 

 same conclusion concerning the Alcyonarian genus Tuhipora, 

 and regarded it as possible that the species of the Zoantharian 

 corals might have to be considerably reduced. 



The Milleporce are exceedingly abundant in the atoll, and 

 the well-marked forms Millepora alcicornis, M. complanata, and 

 M. verrucosa are to be found in plenty. But these well-marked 

 forms are all linked up by intermediate stages, and I have 

 no doubt that all are variants of one species. In the atoll 

 the Milleporce are called Karang gatal — or " itchy corals," for 

 they are capable of inflicting a painful sting when touched. 

 The sting is like that of a nettle, but far more intense, and 

 grave results may follow it. It is curious that of the three 

 forms, M. alcicornis has the power of stinging more severely 

 than the other two, but this fact does not necessitate their 

 taking specific rank, and I do not doubt that there is but one 

 species of Millepora. 1 do not doubt either that all the forms of 

 Pocillopora which are found in the atoll are in reality one species ; 

 and I strongly suspect that there is only one species oiMontipora 

 in Cocos, although its varieties are legion. The species of Madre- 

 pora in the islands are in reality very few ; many diverse forms 

 are certainly identical species, but experimental breeding must 

 finally settle how few these species are. 



It is the same throughout the whole series of the Cocos- 

 Keeling corals ; there is a very limited number of species ; 

 and I would account for the origin of the many varieties, and 

 the present confusion of their nomenclature, by the alteration 

 of environment caused by atoll formation. 



When the origin of the atoll is considered, it will be 

 demonstrated that the whole structure is developed from an 

 original submerged bank, and on this submerged bank I 

 would imagine that the corals represented few species and few 

 varieties. 



The life- conditions all over the bank were fairly uniform, 

 and there lived upon it Pocillopora, MonfApora, and the other 



