174 



GEOLOGY. 



257. Radiates. This class includes the coral animals, 

 hydras, sea-anemones, sea-nettles, echini, or sea-urchins, 

 and star-fishes. The name comes from the ray-like ar- 

 rangement which is so manifest in many of these ani- 

 mals, and exists really in all. It is from this radiate 

 form chiefly that many of them were formerly supposed 

 to be plants, and even now they are often called plant- 

 animals. Examples of them are seen in Fig. 94. Here 



Fig. 94. 



are represented the star-fish, the little hydra, a medusa, 

 a sea-urchin, and sea-anemones. One of the anemones is 

 divided in half, that you may see the interior. They are 

 all inhabitants of the ocean, and many of them, as they 

 are seen sometimes clustered together over a considera- 

 ble space, present, with their beautiful and varied colors, 

 the appearance of a garden under water. They are 



