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outline is changed for a five-sided figure, the angles of 

 which in succeeding species project more and more, and 

 the spaces between become more and more indented, 

 till we arrive at the Starlets, and at length to the Cross- 

 fishes (Asteriadce). The rays gradually becoming longer 

 and more slender, we are brought to those in which 

 they are so lengthened as to resemble the tails of so 

 many serpents, whence they are named Ophiura. In 

 succeeding genera, such as that called Medusa's head 

 (Gorgonocephalus), the central part is still further dimi- 

 nished, and the rays are divided into branches of great 

 length and number. Each ray, soon after its com- 

 mencement, separates into two more ; these again into 

 two others, and so on to an astonishing extent. Up- 

 wards of 2500 ramifications have been counted on a 

 single specimen, presenting a living net, by the con- 

 traction of which any small animal once touched would 

 inevitably be detained. The sucker-feet are no longer 

 found, these animals changing their position by dragging 

 themselves along by their flexible arms. Finally, we 

 have the Feather- stars, which, as we have seen, in their 

 infant condition, and the Lily- stars, which throughout 

 life (as the abundant fossil species in our own land, 

 and that noble one which still exists in the West Indian 

 seas), consist of slender- jointed arms, with feather-like 

 filaments, seated at the free extremity of a tall jointed 



