76 BULLETIN 82, UNITED STATES NATIONAL MUSEUM 



In my first revision of the old genus Antedon published in 1907 I retained adeonae 

 in Antedon as restricted but placed bidens in the new genus Himerometra. 



On the establishment of the genus Oligometra by me in 1908 both adeonae and 

 bidens were referred to it, and both were included in a list of the species of Oligometra 

 published in 1909. Later in 1909 Oligometra bidens was compared with the new species 

 0. (Decametra) studeri. In comparing 0. bidens with this new species I said that the 

 elongate proximal pinnules described in 0. adeonae would serve to differentiate it, if 

 adeonae should be shown to really belong to the genus Oligometra. In a list of the 

 crinoids collected by the German steamer Gazelle published in 1909 I recorded as 

 Oligometra bidens a very small specimen from northwestern Australia. 



In 1909 Dr. Hubert Lyman Clark compared his new species Oligometra (Austro- 

 metra) thetidis with 0. adeonae and 0. bidens. He remarked that in view of our 

 imperfect view of adeonae, and the obvious resemblance between that species and both 

 bidens and thetidis, it seemed to him quite possible that more abundant material will 

 show that the three names belong to a single species. 



In 1910 I examined the types of Lamarck's Comatula adeonae in Paris, very shortly 

 after studying the type of Bell's Antedon bidens in London, and in 1911 published a 

 redescription of adeonae and noted that it is the same as bidens. In my memoir on 

 the crinoids of Australia published in 1911 I gave a synonymy of Oligometra adeonae, 

 including under this species Bell's Antedon bidens and his specimen of Antedon pinni- 

 formis from Dundas Strait, Doderlein's specimens of Antedon bidens from Thursday 

 Island, and the Gazelle specimen from northwestern Australia recorded by me as 

 Oligometra bidens. In giving the differential characters of 0. adeonae, which was com- 

 pared in detail with 0. (Austrometra) thetidis, I used the name bidens throughout 

 instead of adeonae, because the memoir was written before I had seen the types of 

 adeonae and bidens at a time, therefore, when my concept of these forms was based 

 wholly upon the available inadequate descriptions and in recasting the paper, which 

 was then in proof, I failed to change bidens to adeonae. A redescription of the type 

 specimens of Comatula adeonae was given. I remarked that Bell's figure of bidens is 

 very misleading, but a good (photographic) illustration of the species was given by 

 Doderlein. 



In my report upon the crinoids of the Hamburg Southwest Australian Expedition 

 published in 1911 I gave in detail the distribution of Oligometra adeonae on the Austral- 

 ian coasts. In 191 1 also I compared the cirri of my new species Comaster (Comantheria) 

 taviana with those of Oligometra adeonae. 



In my memoir on the crinoids of the Indian Ocean published in 1912 I gave a 

 short synonymy of Oligometra adeonae, including under this species Bell's Antedon 

 bidens, and listed the localities where the species had been obtained including, as hi 

 1911, Baudin Island from where I had seen a specimen in the British Museum in 1910. 

 I remarked that an examination of the types of Comatula adeonae at Paris and of 

 Antedon bidens at the British Museum had shown that in reality the two are the same 

 species. The Alert collection contains specimens identified both as Antedon adeonae 

 and as Antedon bidens. The only adequate figure of the species yet published is that 

 given by Doderlein. 



In my description of Oligometra (Prometra) intermedia published in 1912 I com- 

 pared the cirri with those of Oligometra adeonae. I noted that one of the items of 





