CRIXOIDE.E. 



Crinoids as analogues of the Polypes are lower than the 

 Asteroids, but as allies of the Asteroids are their superiors. 

 An Enerinite is a Polype-like Starfish. Suppose, as Pro- 

 fessor Jones has well suggested, an Ascidioid Zoophyte 

 strengthened by depositions of calcareous matter in its 

 arms and stems, and you have a Orinoid Starfish. In 

 that point of view the latter is a link between the Echi- 

 noderms and the Polypes. But the link is, as it were, 

 lateral — a link of analogy — for the Ascidioid Polypes 

 themselves are higher in their organisation than many 

 Echinoderms. Their digestive system is more developed 

 than that of the Starfishes. In them we see for the first 

 time Echinoderms with two openings to their digestive 

 canal. Their generative system is spread over the tegu- 

 mentary covering of their body and arms, they have 

 tentacular filaments like those of the Ophiurse ; and the 

 pinna; with which the arms are furnished, have the skin 

 so developed on their sides as to enable them to serve as 

 fins wherewith the animal can swim through the water 

 in the manner of the Medusae, whence the name of Pinni- 

 grade Echinoderms which I have applied to them, in- 

 dicative of this mode of progression. 



It will be seen in the account of the Comatula, or 

 Feather-star, that we believe that animal to be fixed and 

 stable, like one of the fossil Encrinites, when it is young. 

 At the same time it is very probable that there are Cri- 

 noids which are stalked throughout life, and that most 

 of the fossil species were of such a nature. Tribes which 

 form a link between one mode of existence and another, 

 generally present examples of both and combinations of 

 both. Thus among the Polypes do we find in the family 

 TubulariadcG the connecting link between the naked and 

 clothed Hydroid Polypes, animals which are naked 



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