and the tentacle bases are beset witli spicules. The spicules are al most always girdled forms, 



with a median band which is bare "i verrucae, and hence appear t<i have an impn 

 girdle. This results in the formation of doublé heads, doublé clubs, doublé spindles, doublé 

 and these forms are quite characteristic of the Gorgonellidae, although not strictly 

 nfined to thi-. family. 



Dichromatism is exhibited in a marked degree, ;i number ol species of Juncella and 

 being characterized by having two color phases, red and white, which do n<>t 

 appear to rellated with sex <>r age. 



The systematic arrangement «>t" this family offers great difficulties, as is apt t<> be the 

 with forms which have been long known. The original descriptions are entirely inadequate, 

 and it is usually impracticable to decide just what forms the authors had before them. None 

 of them paid any attention to the feature that has later been found of prime importance in 

 ric definitions, e. g. the spicules. and confined themsekes almost exclusively t<> general 

 habit, mode of branching, etc, features of almost no generic import whatever. Subsequent 

 writers have very generally ne^lected the discussion of tin- genera in any broad way. 



Milne Edwards and 11 ai m i (1857) recognize the four genera yuncella, Ctenocella, 

 'la and Verrucella, which they separated by modes of branching and character of the 

 calyces. Kolliker (1865) was the first to thoroughly investigate the spicules of this family, and 

 he recognized the genera Gorgonella, yuncella and Verrucella\ but included the genus Riisea 

 of Duchassaing aiul Michelotti, which appears to belon^ to the family Chrysogorgidae. He 

 includes I nus Ctenocella in his genus Gorgonella. 



1 1 70 1 divides the genus yuncella into the three genera yuncella, Ellisella anti Vime- 



nella and restores the genus Scirpearea. He established the genera Nicella, Reticella, Raynerella, 



Phenella and H diana. Two of these, Reticella and Raynerella, appear to belont; to Gorgonella. 



r, (1878) discusses and further defines the genera Gorgonella, yuncella, Ellisella, 



Ctenocella and Scirpearella; and in [887 the same writer gives a careful discussion of tin; 



ra of this family, defining according to modern methods the following genera : Nicella, 



Scirpearea, yuncella, Ellisella, Verrucella, Gorgonella, Ctenocella, Phenelia and ffeliana.The 



two of these genera he defines after Gray without giving the spicule characters which are 



absolutely necessary for modern definition. This treatment is the most satisfactory that has yet 



been presented. and the generic definitions here given are very largely adopted without essential 



modification by the present writer. 



The last general treatment of the family Gorgonellidae as a whole is found in Wright and 

 Studer's Challenger Report, Alcyonaria, 1889, p. 15;,. where the definitions of Studer, as just 

 discussed, are practically adopted in their entirety. They add, however, one genus, Scirpearella 

 and throw doubt on the identity and validity of the old genus Scirpearea of Cuvier, quoting 

 the discussion of Scirpearea mirabilis by Kölliker ' who shows that the name was originally 

 used tor a pennatulid. 



THOMSON and Simpson, in their excellent monograph of the Alcyonaria securcd by the 



1 AnaL-SysL Beschr. der Alcyonarien, Die 1'cnn.iiulidcn, 1872, ]>. 26. 



