Animals Before Man 



Ecliinodermata, contains the echinoderms or sea- 

 urchins, the starfishes and brittle stars, the 

 crinoids or sea-lilies and the sea-cucumbers, the 

 first two familiar to all, the last two much less 

 widely known. The crinoids, so abundant in 

 Carboniferous seas, now nearly extinct and 

 represented by a few species found in deep 

 water, may be roughly compared to a starfish 

 growing upside down on a stalk attached to 

 the middle of its back. As the rays of the star 

 turn gracefully upward and outward, while 

 the stem bears little arms that may pass for 

 leaves, the suggestion of a lily is very strong. 

 The sea-cucumbers, or holothurians, do not at 

 all resemble theii^ radiate brethren, being soft- 

 bodied animals, that look to the untrained eye 

 far more like some strange overgrown worm 

 than any relative of a starfish, although a study 

 of their internal structures has led to the recog- 

 nition of their proper place. 



Then come the Vermes, or worms, a group 

 containing several orders and many members, 

 though in general little known, partly owing 

 to their retiring habits, partly to the unattract- 



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