 Why does the Captain go looking for Purnie?
Safe from the scrutiny of brothers and parents, there was nothing now to stop him from going to the ocean. With everything around him in a state of perfect tableau, Purnie hurried toward the ocean. Further down the beach was a pair of two-legged animals poised in mid-step, facing the spot where Purnie now stood. It was time itself that Purnie had stopped, not the world around him. The tripon thought Purnie's feat was superb. Purnie ran from pillar to post, trying to see and do everything at once. Purnie shrieked with joy at this new frolic and promptly stood on his head.
 The Captain knows Purnie saved the crew.
 The Captain knows that an animal with Purnie's strength is worth a fortune.  The Captian knows an animal that can stop time is worth a fortune.  The Captain knows a radioactive animal is worth a fortune.  The Captain knows Purnie saved the crew.