208 A. JEJ. Verrill — Corals of the Genus Acrojjora. 



have also given additional descriptions of several of my own types, 

 described in 1864-68, and on the type of A. tuMgera (Horn, 1860) 

 I have added descriptions of several new species. 



A number of these types are here figured from enlarged photo- 

 graphs, made by Mr. A. Hyatt Verrill. 



Acropora Oken (restr.). Type, A. numcata. 



Madre23ora (pais) Lam., Syst. Anim., p. 371, 1801 (non Linne, ed. x). Lam, 



Hist. Anim. s. Vert., ii, p. 377, 1816. Dana, Zooph., p. 435, 1846. Edw. 



and Haime, Hist. Corall., iii, p. 132, 1860 {non Ehr.). 

 Acropora (23ars) Oken, Lehr. Naturg., p. 66, 1815 (type, 3d species=^. 7nuri 



cata), 

 Madrepora Brook (with ten subgenera), Cat. Mad. Brit. Mus., i, p. 22, 1893. 

 Isopora Vaughan, Fossil Corals Curacoa, etc., p. 68, 1901. Stony Corals Porto 



Eican Waters, Bull. U. S. Fish Comm. for 1900, ii, p. 812, 1901.* 



On pages 110-113 and 164,1 have given reasons for displacing 



Madrepora as the name of this genus, and for the substitution of 



Acropora Oken. 



In brief they are these: 



1st. No recognized species of this genus was included in Madrepora 

 by Linne, in his Syst. Nat., ed. x. 



2d. M. muricata (auth.), which originally included all the known 

 species of Acropora, was put under Millepora in the ed. x, 

 though placed in Madrepora in ed. xii, as also by Pallas. 

 Therefore it cannot properly be taken as the type of Madre- 

 pora if the ed. x is to be used as the starting point of the 

 binomial system. 



3d. Lamarck, in 1801, gave only two species as examples of Madre- 

 pora, viz : M. muricata and M. porit.es. The latter was 

 made the type of the genus Porites by Link, in 1807, other- 

 wise it might have been adopted for the type of Madrepora. 



4th. Oken, in 1815, proposed the genus Acropora, including three 

 species, of which the third was A. muricata. This can be 

 adopted as its true type, because the second had already 

 been placed in Porites by Link, 1807 ; and the first was 

 placed in Pocillopora by Lamarck, in 1816. This leaves the 

 name Acropora clearly available for the great genus of which 

 A. muricata is the type. 

 The genus Acroj^^ora (restr.) is characterized by the presence of at 

 least two forms of corallites. In all branched forms there is a sym- 



* Mr. Vaughan has recently aiathorized me to state that he now accepts the 

 name Aci^opora for this genus, instead of Isopora. See p. 206. 



