National Geographic : 1934 Jun
1'fnotograph by Dr. Koy Waldo Miner BLEACHING A CORAL; IT WEIGHS A TON AND A HALF! Such purplish red domes, the densest and heaviest yet discovered, grow abundantly in the West Indies and play an important part in reef forma tion. After being wetted, the outer layer of animal tissue sloughs off, expos ing the white limestone skeleton. W11. 1!.Hill THESE ARE THESTONY "BONES" OFBUSY WORKERS A piece of dead coral, here magnified, ishoneycombed with cell-like struc tures of limestone. Each was made byaminiature chemical factory, atiny, tentacled polyp (see text,page 713). The cuplike opening contained the polyp's entire body, withmouth and stomach cavity.