INTRODUCTION. 



In the Histoire Naturelle des Coralliaires of Milne-Edwards there will be found a succinct 

 but accurate account of the various memoirs on the Alcyonaria which had been published 

 prior to 1857, and as this work has lost none of its importance to the student of this 

 group, we refer to its pages for a summary of the labours of the older writers. To 

 Milne-Edwards, Dana, and Kolliker we are principally indebted for our knowledge of the 

 classification and systematic position of the Alcyonaria, and but few attempts have been 

 made to revise the systems under which these biologists arranged the forms known to 

 them. Nevertheless during the last few years the number of new genera and species 

 described has been very great, and at the same time very large additions have been made 

 to our knowledge of the structure, growth, and development of many of the recent forms. 

 While it does not seem necessary to give a complete bibliography of the group, such 

 being already published in the various records of zoological literature, special 

 reference must be made to the writings of Gray* and Verrill,^ to the excellent monograph 

 of Klunzinger^ on the Corals of the Red Sea, and to the splendid memoirs of those of the 

 North Sea by Koren and Danielssen,* nor must the writings of Marenzeller,^ Marion," 

 and Ridley' be overlooked, as equally with the others advancing our knowledge of new 

 species, while that of the minute structure of the group has been greatly furthered by 

 the able researches of de Lacaze Duthiers,^ Kolliker,' Moseley," Kowalevsky and Marion," 

 Hickson,'^ Herdman," Danielssen, von Koch," and Pourtales.'* 



' J. E. Gray, Catalogue of Lithophytes or Stony Corals in the Collection of the British Museum, 1870, and very 

 numerous papers in the Proc. Zool. Soc. Lond.. and the Ar^n. mid Mag. Nat. Hist. 



' The various Memoirs of Professor Verrill will be found quoted in full in the following Description of Genera. 

 ' Dr. C..B. Klunzinger, Die Korallthiere des Rothen Meeres, Berlin, 1877. 



* J. Koren and D. C. Danielssen, Nye Alcyonider, Gorgonider og Pennatulider tilhrende Norges Fauna, Bergen, 1883. 

 D. C. Danielssen, Den Norske Nordhavs-Expedition, 1876-78 ; Alcyonida, Christiania, 1887. 



° E. V. Marenzeller, in Denkschr. math-nat. CI. d. k. Akad. Wiss. Wien, Bd. xxxv., 1877. 



* A. F. Marion, Comptes rendus, t. xciv., 1882. 



' S. 0. Ridley, Zool. Coll. of H.M.S. " Alert," 1884, and papers in the Proc. Zool. Soc. Lond., and in the Ann. and 

 Mag. Nat. Hist., 1881-1887. 



' H. de Lacaze Duthiers, Hist. Nat. des Corail., Paris, 1863. 



^ A. Kolliker, Icones Histiologicfe, Leipzig, 1863, and numerous Memoirs as quoted hereafter. 

 " H. N. Moseley, Phil. Trans., vol. clxvi., 1876 ; and Zool. Chall. Exp., part vii., vol. ii., 1881. 

 1' Alex. Kowalevsk and A. F. Marion, Comptes rendus, t. xcv., 1882 ; Ami. Mus. d'hist. nat. de Marseille, 1883. 

 '2 S. J. Hickson, Phil. Trans., vol. clxxiv., and Quart. Journ. Micr. Sci., 1883. 

 '^ W. A. Herdman, Proc. Roy. Phys. Soc. Edin., vol. viii., 1884. 



" G. V. Koch, Morphol. Jahrb., vols, iv., v., vi., vii., and viii., 1878-1883 ; Mitth. Zool. Stat. Neapel, Bd. iii., 1882. 

 Die Gorgoniden des Golfes von Neapel, &c., 1887. 



15 L. F. de Pourtales, Bull. Mus. Comp. Zool., vols. v. and vi., 1878-1881. 



(zool. chall. EXP. — PART LXIV. — 1889.) Sss h 



