THE RECENT CRINOIDS OF THE COASTS OF AFRICA. 



By Austin Hobart Clark, 



Assistant Curator, Division of Marine Invertebrates, U. S. National Museum. 



HISTORY. 



The history of the study of the recent crinoids inhabiting the 

 coasts of Africa can be stated in a few words. With but three 

 exceptions all the references to African crinoids are only incidental 

 incorporated in works sometimes restricted to the echinoderms alone, 

 but more commonly very general in scope. Thus while the titles of 

 books and papers number about seventy, from each one only a small 

 amount of information is gained, and an adequate conception of 

 African crinoids as a whole can be acquired only by an amount of 

 labor totally incommensurate with the sum of the knowledge gained. 



The first crinoid known from African waters was described from 

 Mauritius in 1816 by Lamarck under the name of Comatula carinata. 

 Lamarck adopted the name carinata from Leach, who in the previous 

 year had diagnosed, in a very insufficient manner, his Alecto carinata, 

 which Lamarck thought might turn out to be his species. 



In 1817 the portion of Savigny's Description de l'Egypte dealing 

 with the echinoderms was published, and in it were figured two 

 comatulids from the Red Sea, one of which was designated by 

 Audouin as " Comatula sp.," the other as " Comatula rnultiradiata." 

 There is no further reference to the first of these figures, which rep- 

 resents Tropiometra encrinus; but in 1836 de Blainville copied the 

 second in the atlas to his Manuel d'Actinologie. In doing this he 

 made a curious mistake, for the plate is lettered "Comatula adeonse," 

 though in the text the description of Comatula adeonx is taken from 

 Lamarck, and the species is correctly said to have ten arms. In the 

 following year the Penny Encyclopedia copied de Blainville's account 

 of Comatula adeonx, multiradiate figure and all, and the same slip 

 was made by Knight in his Natural History, published in 1867. 



Riippel, in the course of his travels, found in the Red Sea an inter- 

 esting multiradiate comatulid upon which he bestowed the manu- 



Proceedinqs U.S. National Museum, Vol. 40— No. 1808. 

 80796°— Proc.N.M.vol.40— 11— 1 1 



