144 



SOME WONDERS OF THE SEA. 



instead of being on the outside of the stony deposit, are 

 within it, forming it into tubes, in and out of which they 

 can freely project the tentacle by which they obtain 

 food. 



At Fig. 1 is seen a mass of Organ-pipe Coral, consider- 

 ably reduced, so as to show its general appearance. At 

 Fig. 2 a portion is given of the natural size, so as to show 

 the arrangement of the tubes. Fig. 3 represents two of 



ORGAN-PIPE CORAL. 



the tubes enlarged, showing the " head," as the tentacle 

 mass is called, as it appears when it is just protruded, 

 and enabling the reader to understand the mode in which 

 the tentacles are pressed together when within the tube. 

 Fig. 4 gives a further magnified view of a single head, 

 and Fig. 5 shows the appearance of a single individual 

 when fully expanded, seen from above, and considerably 

 magnified. 



These beings enter largely into the constituents of 



