STAR-FISH AND SEA-URCHINS. 269 
it may very likely attach its uppermost rays to it, 
and then, letting go its other attachments, swing 
from the one support to the other. The activity 
and co-ordination manifested in these acrobatic 
movements are surprising, and give to the animal 
an almost intelligent appearance. 
In Astropecten the ambulacral feet have become 
partly rudimentary, inasmuch as they have lost 
es 
ANNAN 
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| _LSSSpoeeeecn 
| 
| 
WAAAY 
Fig. 43.—Natural movements of a Star-fish on reaching the surface of water. 
their terminal suckers (Fig. 44). These Star-fish, 
therefore, assist themselves in locomotion by the 
muscular movements of their rays, while they use 
their suckerless feet to run along the ground some- 
what after the manner of centipedes. It is to be 
noticed, however, that although the feet have lost 
their suckers, the Star-fish is still able to make them 
adhere to solid surfaces in a comparatively inetticient 
