SUBORDER ALCYONARIA. 589 



traded state the upper surface is sprinkled with minute white dots, 

 and larger substellate spots, ahout three-fourths of a line in diameter : 

 the former, under the microscope, consist of eight points, and are, 

 probably, young budding polyps; the larger are the adult polyps, and 

 are about a line apart. The general surface is filled with very minute 

 calcareous spicula, seen only under a magnifier. Below, the zoophyte 

 is venosely striate ; and the caudal appendage is longitudinally sulcate 

 and transversely fine rugate. The usual size of the specimens from 

 the West Indies and Carolina coast, is about an inch in breadth, with 

 the caudal appendage two-thirds of an inch long. 



Specimens, probably of this species, were obtained by the Expedition 

 at Rio Janeiro. They were collected by J. P. Couthouy, and figures 

 I, I a, plate 57, are from his drawings. The expanded polyps have 

 the rays light yellow, with a row of red dots along the margin, at the 

 base of the fringe of long papillaB. The general colour of the zoophyte 

 is a dull reddish-purple. Only a more thorough examination of the 

 polyps of the R. americana, will determine the identity of these species. 

 The author has examined a specimen from Rio, in alcohol, but it 

 was in too imperfect a condition to decide the question. 



Akyonium agaricum, Linn, Gmel., 3811. , Schweigger, Beobacht. pi. 2, figs. 10, 



Pennatula reniformis, Ellis and Sol., 65. 11 ; giving dissections ; and Handb.,435. 



, Pallas, Elenchus Zooph., 374. , Blainville, Man. d'Actin., 518. 



, Shaw, Miscell., iv., tab. 139. , Ehrcnberg, op. cit., G. xxxiv., sp. 1. 



Renilla americana, Lamarck, ii. 646. 



The Rcnilla violncea, of Quoy and Gaymard, may be a different species, but the only 

 distinguishing character hitherto given is an emarginate or concave front margin. The 

 polyps were of a yellow colour, with a very short fringe, and perhaps were not fully ex- 

 panded. (Quoy and Gaymard, Voy. de 1'Uranie, pi. 86, figs. 68. Regne Animal, 

 Paris, 1837, pi. 91, fig. 3; a copy of Quoy and Gaymard's figure; Ehrenberg, op. cit., 

 Gen. xxxiv., sp. 2.) 



GENUS II. VERETILLUM. CUVIER. 



PennatulidcB crassce, oblongo-cylindricce, non ramosce ; polypis sparsis, 

 retractilibus. 



Stout cylindrical, and not branched ; polyps scattered, retractile. 



148 



