532 PROF. F.J. BELL ON THE COMATULlD.li. [JuilC 6, 



1 A'RP - is the formula for a multiradiate' Actinomelra with its 

 radial and palmar (though not its distichal) axillaries syzygies, 

 with a syzygy on its first brachial, with less than 13 cirri, and more 

 than 40 cirrus-joints. 



When a character frequently though not always obtains, the 



corresponding letter is put within brackets : thus 3AR(P) ^ would 

 be tlie formula of a species of Antedon in which, though the radial 

 and third brachial joints were always syzygial, the palmar axillary 

 was only sometimes so ; in those rare cases in which divisions 

 extend bevond the palmars, I have made use of the symbols P' and 

 P". 



In the Hsts that follow, the greater number of described species of 

 Antedon and Actinometra will be found enumerated and their 

 formulae given ; in addition there are given the names and formulae 

 of some new forms that have been lately collected by Dr. Coppinger, 

 of H. M.S. 'Alert,' the descriptions of which will be shortly published 

 elsewhere. 



As in the paper on Asterias, I have given only one reference to 

 the description of each species. In addition to the heavy debt which 

 I owe to the published writings of Mr. P. Herbert Carpenter, I 

 have to add that the formulae of some of the species of Johannes 

 Miiller are given with more satisfactory knowledge than the rest, 

 owing to the fact that Mr. Carpenter, in a manner of which I know 

 not whether the scientific liberality or the amiable friendliness is the 

 mure remarkable, has provided me with copies of the notes made 

 by him on the specimens which formed the bases of Miiller's de- 

 scriptions. Mr. Herbert Carpenter's two papers referred to in the 

 following hsts are to be i'ound (i.) in the ' Notes from the Leyden 

 Museum,' vol. hi., and (ii.) in the 'Bulletin of the Museum of 

 Compar. Zoology,' ix. no. 4. The references to Johannes Miiller's 

 ' Ueber die Gattung Comatula ' refer to the pagination of the 

 separate copies ; Count Pourtales's papers are to be found in, respec- 

 tively, (i.)Bull. M. C.Z.no. G, (h.) B. M. C. Z. no. II, and (ih.) B. 

 M. C. Z. V. no. 9. The other references will explain themselves. 



1. Lists of Described Species. 



(a) Antedon. 



1. adeonce, Miill. p. 1.5. 



2. alata, Pourt. hi. p. 21.5. 



3. armata, Pourt. ii. p. 356. 



4. articulata, Miill. p. 27. 



5. bimaculata. Carp. i. p. 186. 



6. brevieuneata, Carp. i. p. 187. 



1 When D or P appear in a formula it is clear the sijecies must ha\e more 

 than 10 rays, because of the meaning of the words those letters represent ; 

 where, however, neither clistichals nor palmars present a syzygial joint, it will be 

 necessary to make use of the mathematical sign for the square root to mark the 

 fact of its being a multiradiate species. 



