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substances between tide marks. As they burrow with great ease 

 in chalk, it is natural that they should be abundant on the fore- 

 shore at Brighton in the projecting boulders and in the chalk floor. 



By chipping off a piece of chalk with a cold chisel, a group 

 can easily be removed and transferred to a jar of sea water at 

 home in which their doings can readily be observed. Each one 

 seeks to improve its position for getting a good supply of food by 

 erecting a little turret over one of the entrances to its U shaped 

 tunnel in the stone. Then the tentacles can reach farther for 

 food without the naked body being exposed to possible injury. 



It is highly interesting to watch these little creatures feed- 

 ing. A little finely powdered biscuit dropped into the water will 

 provide the feast. The watchful animals soon see what has been 

 done, and commence excitedly to wave their highly elastic ten- 

 tacles, as if in glee, but really to secure the food. Any particles of 

 solid matter touching the tentacle are seized and passed to the 

 mouth along a groove on one side of the tentacle by the cilia 

 arranged in pairs thereon. 



If the substance be edible it is at once consumed ; if not, it 

 is utilized as building material for the enlargement of the turret. 



When, as sometimes happens, two animals simultaneously 

 grasp the same crumb, a severe struggle for the possession takes 

 place. Each anchors itself firmly in its burrow, and then tugs 

 away with all its might. The turrets yielding to the strain, 

 bend inward, and the part of each tentacle concerned in the 

 struggle appears perfectly rigid. Then, when the strength of 

 one or other of the contestants is exhausted, the two animals 

 suddenly slip back out of sight and the tubes again become erect. 



