A MONOGRAPH OF THE EXISTING CKINOIDS 25 



Comaster (genotype Comatula multiradiata Lamarck, 1816 = Asterias rmdtiradiata 

 Linne) including — 



Comaster borneensis. Comaster mariae. 



Comaster coppingeri. Comaster multiradiata. 



Comaster discoidea. Comaster sentosa. 



Comaster fimhriata. Comaster imoensis. 



Comaster lineata. 



Comatula as here understood is characterized by having all the synarthries 

 replaced by syzygies. 



In Phanogenia synarthries are present between the first two post-radial ossicles 

 and all the arm divisions are of the interpolated type. 



In Comaster synarthries are likewise present between the first two post-radial 

 ossicles, and the first arm division is interpolated, while those following are all 

 extraneous. 



In Isocrinus naresianus and in the species of Endoxocrinus the arm division is 

 interpolated as in most of the comatuhds. In Isocrinus decorus and in I. blakei 

 the Z pair always remains the first two ossicles beyond the costal axillary and the 

 further arm branching is extraneous. In Metacrinus the Z pair, as in the Penta- 

 metrocrmidae, consists of the first two ossicles following the radials. 



The recent pentacrinites are distributed in four genera as follows: 



Metacrinus (genotype M. wyvillii P. H. Carpenter, 1884); Z, and Z2 the first 

 two post-radial ossicles, not repeated; all arm division extraneous; second post-radial 

 ossicle not an axillary, but bearing a pinnule; basals very broad, forming, when 

 viewed dorsally, a rounded pentagonal figure; infrabasals large and prominent 

 (found in M. serratus by Doderlein and in M. superbus and in several specimens 

 [all dissected] of M. rotundus by the author) . The included species are : 



Metacrinus acutus. Metacrinus rotundus interruptus. 



Metacrinus angulatus. Metacrinus serratus. 



Metacrinus cingulatus. Metacrinus stewarti. 



Metacrinus costatus. Metacrinus suluensis. 



Metacrinus moseleyi. Metacrinus superbus. 



Metacrinus murrayi. Metacrinus superbus borealis. 



Metacrinus murrayi nobilis. Metacrinus superbus tuberculatus. 



Metacrinus murrayi timorensis Metacrinus tuberosus. 



Metacrinus nodosus. Metacrinus varians. 



Metacrinus rotundus. Metacrinus wyvillii. 



Hypalocrinus (genotype Pentacrinus naresianus P. H. Carpenter, 1882); Zi and 

 Z2 repeated at least once; the second postradial joint an axillary; Z, and Z2 the 

 third and fourth postradial ossicles; infrabasals ?; one interpolated series only; 

 basals broad, forming, when viewed dorsally, a rounded pentagonal figure. The 

 included species is : 



97298—31 3 



