A MONOGRAPH OF THE EXISTING CRINOIDS 223 



Antedon acuticirra, and in discussing this mentioned another specimen from Sydney 

 in the Copenhagen Museum bearing the manuscript name Antedon australis given it 

 by Lutken which had some resemblance to it. He also described two other species, 

 Antedon ludovici and A. bipartipinna, both of which were based upon single specimens 

 from Hongkong. In the key to the species discussed in the paper he included Antedon 

 acuticirra and A. ludovici under the headings "Rays divide three times. First division 

 of three joints, the axillary with a syzygy; second of two joints, the axillary without 

 a s y z ygy [that is, IIBr series 4 (3+4) and IIIBr series 2]" and also "Fifty or more 

 cirrus-joints. Lower pinnules similar on all the arms." The characters by which he 

 distinguished acuticirra from ludovici were that in acuticirra the terminal cirrus seg- 

 ments are smooth, while in ludovici the distal cirrus segments have dorsal tubercles. 

 As given in the key the chief characters of A. bipartipinna are "Rays divide three times, 

 each division of three joints, the axillary with a syzygy [that is, the IIBr and IIIBr 

 series are both 4 (3+4)]," while the cirri are long and stout with an imperfect terminal 

 claw and smooth terminal segments. 



In the following year Carpenter gave specific formulas for Antedon acuticirra, A. 

 ludovici, and A. bipartipinna. 



In the Challenger report on the comatulids published in 1888, Carpenter gave 

 emended specific formulas for Antedon acuticirra, A. ludovici, and A. bipartipinna, and 

 mentioned (in discussing Antedon [Thalassometra] bispinosa) that in A. acuticirra the 

 "radial axillaries" (the IBr 2 ) come into contact above the depressed lateral portions 

 of the second radials (the IBr^. As none of these forms had been secured by the 

 Challenger Carpenter did not discuss them in detail, merely including them in the key 

 to the species of the "Savignyi group." In this key he gave acuticirra as having the 

 cirrus segments smooth and longer than broad, with no opposing spine, while in ludovici 

 the cirrus segments are broader than long, the outer have faint tubercles, and the 

 penultimate has an opposing spine. In the key Antedon bipartipinna was paired with 

 A. philiberti, these two forms being, according to Carpenter, distinguished from all 

 the other species in the "Savignyi group" by the possession of IIIBr 4 (3+4) series. 

 Of A. bipartipinna he said that there are nearly 60 cirrus segments of which the outer 

 are longer than broad and quite smooth, while the terminal segments of the lower 

 pinnules are much smaller than the basal ones. He gave A. [Heterometra] philiberti as 

 having 45 cirrus segments of which the later are short and spiny. 



In studying the collection of comatulids made by Prof. J. Brock at Amboina, 

 Dr. Clemens Hartlaub found 12 specimens that he at first considered as representing 

 a new species. He accordingly prepared a detailed description of them, but later he 

 decided that they belonged to the form which had been described by P. H. Carpenter 

 as Antedon ludovici. In 1891 he published the description he had drawn up under that 

 name, in which he included Antedon acuticirra as a synonym and A. bipartipinna as a 

 probable synonym. He said that he had sent a specimen from Brock's Amboina 

 collection to Carpenter, who had pointed out that it was apparently identical with his 

 Antedon ludovici from Hongkong and that he convinced himself of the correctness of 

 this conclusion by an examination of the type specimen of ludovici at Hamburg. He 

 gave a detailed comparison between his Amboina specimens (which really represent 

 Heterometra amboinae; see page 297) and the type specimen of Antedon ludovici. He 

 regarded the Chinese form (ludovici) to which he assigned also the type specimens of 



