In a strong debut by a Dutch author-artist, an inveterate butterfly collector has a fantastic dream about chasing a marvelously beautiful specimen as far as the moon. He wakes with the new idea of setting his real specimens free: ``Collecting is for bored people.'' Still, he decides not to give up the fun of the chase. Gracefully told, if predictable; best are the spacious watercolors, including many imaginative details and depicting Old Bear with warm good humor. (Picture book. 4-8)