A. E. Verrill — Corals of the Genus Acropora. 211 



Notes on the Distribution and Subdivisions of Acropora. 



The following list contains most of the species that I have per- 

 sonally studied, with their principal recorded localities. It is proba- 

 ble that most of the East Indian species have a very wide distribu- 

 tion, though at present recorded from only a few localities, or per- 

 haps from only one. Many species are known to range from 

 Singapore to Tahiti or the Fiji Is., or even to the Great Barrier 

 Reef, and to the Red Sea. Probably many others will be found to 

 have as great a range, when more fully collected. 



This wide distribution, and even a greater one, is well known to 

 occur, also, in the case of numerous mollusks, echinoderms, etc., 

 characteristic of the Indo-Pacific fauna. 



But it is probable that local variations, especially in growth-forms, 

 will occur in the same coral when found in widely separated localities, 

 as is the case in other groups. Probably many of these growth- 

 variations have been described as distinct species, but without a 

 large series of specimens it is not possible to determine this, in most 

 cases. The variations of A. muricata in the West Indies should 

 serve as a caution against overestimating the importance of mere 

 forms of growth in corals of this genus and others. 



Many mollusks and echinoderms of the East Indian fauna range to 

 Australia, Africa, and even to the Hawaiian Islands. But I have 

 never seen an authentic specimen of Acropora from the Hawaiian 

 Islands. Local collectors assert that the genus does not occur there. 

 But great quantities of corals, etc., are brought from the Polynesian 

 Islands to Honolulu by the missionary vessels and sold there as 

 curiosities. 



Many corals, seen in collections, labelled as from the Hawaiian 

 Islands, have been obtained in this way, but are natives of the 

 Caroline Islands, Ebon Island, the Kingsmills Islands, etc. This is 

 especially the case with ornamental species, like Stylaster elegans V., 

 Distichopora nitida, etc. 



Probably this was the case with the several species of Acropora, 

 recorded from the Hawaiian Islands by Brook. Their occurrence 

 there certainly needs confirmation, for in the large authentic col- 

 lections of corals that I have studied from those islands no Acropora 

 has occurred. 



Specimens of corals are brought to Singapore from long distances 

 by the natives, for sale, and thus may be recorded from there 

 erroneously. 



Similarly, species of this genus have been recorded from St. 

 Helena, the White Sea, etc., where they probably do not live. 



