Anthozoa (incl. Hydrocorallia). C. Hydrocorallia. 35 



Gravier( 3 ) describes the burrowing of Scytaliopsis. Specimens placed on 

 the sand, after a variable time, bend the end of their stalk downwards, the 

 stalk becomes turgid, liquid being forced into it from the general cavity, and 

 is thus enabled to make a depression in the sand. After a short time the 

 liquid in the stalk flows towards the opposite extremity and then back again 

 into the stalk; by this repeated ram-like action the stalk forms a cavity for 

 itself in the sand, the polyp-bearing part gradually raises itself as the stalk 

 enters the sand and finally almost the whole animal disappears into the burrow. 

 The polyp-bearing region must be constantly immersed in water, the burrowing 

 process is not completed if the animal be only partly covered with water. The 

 stalk is the essential factor in burrowing, if it be sectioned or cut the animal 

 remains inert upon the sand. - - See Gravier( 9 ). 



G. Hydrocorallia. 



For Millepora see, supra p 30, Jones. 



