188 MR. P. H. CARPENTER ON THE GENUS SOLANOCRINTTS 



stem and the united radial s he found (in most of his specimens) 

 five basal pieces of variable size (PI. IX. figs. 1, 2, PI. X. figs. 14, 

 15). These are not visible in most recent Comatulce, but were 

 apparently represented in an exceptional species from the Indian 

 Ocean, which Groldfuss referred to C. multiradiata, Lam. # The 

 specimen was dissected and described by him ; but no similar 

 one has since been found. It seems to have had basals analogous 

 to those of Solanocrinus ; but Groldfuss described its centrodorsal 

 as consisting of one piece only, while he believed that of Solano- 

 crinus to be made up of three or more anchylosed rings. 



Although he recognized the great resemblance between this 

 Comatula (which he supposed to be the type of many others) and 

 the forms described by himself as Solanocrinus, yet he placed the 

 latter among the stalked Crinoids for the reasons already given ; 

 though he mentioned at the same time that they were probably 

 not " festgewiirzelt " any more than the Comatulce are. 



Agassizf erected the Comatula multiradiata of Lamarck into a 

 new genus, Comaster, distinguished by its having the arms rami- 

 fied instead of simply forked. He naturally included in this 

 genus the many-armed specimen dissected by Goldfuss, who 

 adopted this name for it J, apparently under the impression 

 that all the multiradiate Comatulce possessed external basals. It 

 was this character, however, and not the ramification of the arms, 

 that he regarded as distinctive of the genus Comaster. This defi- 

 nition of Comaster was employed by Muller§, though, oddly 

 enough, he ascribed it to Agassiz ; and in this mistake he has 

 been followed by most later naturalists . It must be remembered, 

 therefore, that Comaster, Ag.,is by no means the same as Comas- 

 ter, Groldf. The latter type is the one with which we are especi- 

 ally concerned ; and although Miiller united it with Solanocrinus, 

 Goldfuss continued to regard it as distinct on account of the sup- 

 posed differences between their respective centrodorsal pieces ; 

 and expressly stated that it had no fossil representatives. Both 

 were distinguished from the ordinary Comatulce by the presence 



* Tom. cit. p. 202. 



t " Prodrome d'une Monographie des Radiaires ou Echinodermes," Ann. des 

 Scien. Nat. 2 e serie, Zool. vii. p. 257. 



\ " Beitrage zur Petrefactenkunde," Nov. Acta Acad. Leop.-Carol. Nat.-Cur. 

 xix. a. p. 348. 



§ " Ueber den Bau des Pentacrinus caput medusa" Separat-Abdruck aus den 

 Abhandl. d. Berlin. Akad. 1843, p. 27. 



