2 



piiOF. P. MAHTiN Duncan's revision op the 



merits have been recognized by every competent critic. It 

 revised the genera up to tlie date of 1857-1860, and contained 

 descriptions o£ every species and its synonymy. 



Since the publication of this standard work M. de Promentel 

 has brought out a book * which relates to fossil forms only ; 

 but all the other additions to the knowledge of the suborder 

 have appeared in reports, monographs, and multitudes of essays, 

 which are scattered amongst the scientific publications of Europe, 

 America, India, and Australia. The number of new genera and 

 species recorded has been great ; and altbougb those relating to 

 tbe deep-sea and reef-building faunas have been numerous, they 

 have been surpassed by the forms from nearly every geological 

 formation in every quarter of the globe. 



Careful morphological investigations have increased the know- 

 ledge of the minute structures of the Madreporaria ; and Dana, 

 J. Haime, L. Agassiz, Yerrill, Lacaze-Dutbiers, and especially 

 H. N. Moseley, have so enlightened the views of naturalists, that 

 very considerable changes have already been made in the primary 

 classificatory groups of the Corals. Palaeontologists and naturalists 

 have endeavoured to assist classification by examining the solid 

 structures ; and tbe researches of Pourtales, E. Pratz, Lindstrom, 

 Klunzinger, and Koch have necessitated serious revision of old 

 conceptions. It is evident, however, that the purely classifi- 

 catory work has too often been attempted by some palaeontologists 

 wbo have not studied the recent faunas, and occasionally by natu- 

 ralists who have not had experience in the details of the extinct 

 forms. 



It is proposed in this revision to omit all reference to the 

 group of Corals called the Eugosa by Edwards and Haime. 



As the synonymy of the genera which had been described up 

 to 1860 was given by Edwards and Haime in their great work, 

 this revision will only take it up from that date. 



Only the principal sections, families, and genera are con- 

 sidered in this revision ; species are not included. A few sub- 

 genera are admitted in the classification, and the plan of linking 

 genera under alliances has been adopted. A certain number of 

 alliances will be found in each subfamily or family, and usually 

 they are fairly natural, and rarely too artificial in their nature. 

 It will be found that some of the great groups of the Madreporaria 



* ' Introduction a I'etude des Polypiers fossiles,' Paris, 1858-61 



