ANIMAL KINGDOM. 315 



Cirripeda to the radiated system of Asterias be conducted 

 in feny manner similar to this, it will then only be neces- 

 sary to investigate the nature of the chasm that so widely 

 separates them. 



I have only one thing more to observe on this subject, 

 namely, that if the radiated disposition of the internal and 

 external parts of the genus Coronula forcibly reminds 

 us of the genus Eckvius, and if Linna?us describes it as 

 " testa Jigura Echini absque radiis," it ought moreover 

 to be recollected that the articulated feet of a Cirripede 

 are not" absolutely invisible among the Radiata. It was 

 even upon this principle that M. Latreille detected their 

 affinity. " Les Comatides" says this naturalist, " et les 

 Emyales, genres de cette division classique (Radiaires), 

 nous montrent positivement des parties analogues aux bras 

 des Cirrliipedes, celles quon distingue sous le nom dc 

 rayons articuUs, et quelqucfois dichotomes tels que ceux 

 des Euryales. On en voit autoiir de la boiiche dans les 

 Comatules." 



Radiata. 



The Echini deserve attention, as after them no Radiated 

 animal has two apertures to its intestinal canal ; they lead 

 immediately by means of the genus Scutella to the Stelle- 

 rides of Lamarck, a group which is the same with the 

 genus Asterias of Linneeus. Those animals which com- 

 pose the modern genus Ophiurus make the passage vei-y 

 easy and gradual from the true Starfish to Medusa Andro- 

 meda, and M. frondosa, which form part of the genus Cas- 

 iiopea of Peron. This naturahst, who has contributed 

 more than all others together towards our acquaintance 

 with the nature of the Aledusee, has so well described the 

 singularity of these animals, that I cannot do better than 



