CORALS FROM MURRAY, COCOS-KEELING, AND FANNING ISLANDS. l6l 

 Species of Acropora reported by Brook from Australia — continued. 



The total number of species definitely reported from Australia is 74, to which 

 I have added the names of 4 species the locality of which is not given or which are 

 questionably referred to Australia. I have marked with an asterisk (*) the names 

 of 18 species which are specially considered in the present paper; and have indi- 

 cated with a dagger (f) those of Dana's species of which the types are in the U. S. 

 National Museum. It is not practicable here to review the species of Acropora 

 reported from the Great Barrier Reef, as such a task is probably not possible without 

 a critical study of Brook's types and of the other specimens examined by him. 

 However, I will say that I doubt if half as many species as he recognized will be 

 found valid. Recent studies, especially those by von Marenzeller, of the variation 

 in the corallum of species of Acropora have shown it to be enormous. It appears 

 that Brook has often described as species the vegetational variants of the same 

 species; but without critical study of large suites of specimens it is hazardous to 

 attempt to revise the synonymies. It is highly improbable that Brook is correct in 

 his reference of certain Great Barrier Reef specimens to the same species as that 

 to which the West Indian members of the genus belong. 



