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BULLETIN 82, UNITED STATES NATIONAL MUSEUM 



Liitken also said that the number of ambulacral furrows abutting on the mouth, 

 the character used by Miiller in differentiating Actinometra, is of no importance at all. 

 But the anal tube in all the species of Actinometra has a central or subcentral position 

 and the anal area occupies the larger portion of the disk. Using this feature as a 

 primary differential character, Doctor Liitken said that he had never encountered a 

 doubt whether any type should be referred to Antedon or to Actinometra, although he 

 had examined a great number of specimens and of species. 



Carpenter confirmed Liitken's observations and discussed at great length the 

 characters presented by the species of Actinometra. He referred to this genus Solaris 

 Lamarck, pectinata Linne, brachiolata Lamarck, robusta Liitken (manuscript name), 

 rotalaria Lamarck, polymorpha, sp. nov., trichoptera J. Miiller, wahlbergii J. Miiller, 

 fimbriata Lamarck, multifida J. Miiller, multiradiata Linn6, parvicirra J. Miiller, 

 and bennettii J. Miiller, and also, with a query, purpurea J. Miiller, rosea J. Miiller, 

 echinoptera J. Miiller, and meridionalis E. C. and A. Agassiz. The last four he knew 

 only from descriptions. Seven species described by Miiller he was unable to examine 

 and from the descriptions he could not obtain any information regarding the position 

 of the mouth or the character of the oral pinnules. Four of these seven, cumingii 

 J. Miiller, japonica J. Miiller, novae-Guineae J. Miiller, and timorensis J. Miiller, 

 belong to the Comasteridae. 



In 1884 Carpenter distributed the species of Actinometra among eight specific 

 groups which were based upon the type of arm division. These specific groups were 

 as follows: 



A. Ten arms only; a synarthry between 



the first two brachials Group of Actinometra meridionalis. 



B. IIBr 2 (1+2) Group of Actinometra jukesi. 



C. IIBr 2 Group of Actinometra pulchella. 



D. IIBr 4 (3+4) Group of Actinometra parvicirra. 



E. IIIBr 2 (1+2) Group of Actinometra typica. 



F. IIIBr 2 l__ .__ Group of Actinometra stelligera. 



G. IIIBr 3 (2 + 3) . . Group of Actinometra multiradiata. 



H. IIIBr 4 (3 + 4) Group of Actinometra bennetti. 



He mentioned these divisions of the genus merely to illustrate the fact that in the 

 single species Neocrinus decorus various types of IIBr and IIIBr series occur which 

 are specially characteristic of different groups of species in Actinometra. 



In 1888 Carpenter divided the genus Actinometra into eight specific groups 

 included in four series, as follows: 



Series I: IBr series 2 (1+2); first arm syzygy between brachials 1+2: 



1. Ten arms Solaris group. 



2. IIBr series 2 (1+2) Paucicirra group. 



3. IIBr series 4 (3 + 4) Typica group. 



Series II : IBr series 2 ; 1 arms : 



4. IBr 2; 10 arms Echinoptera group. 



