Answer:
A spent round or a slimy critter.
A pony trots his way through the world on these.
My first is in window but not in pane. My second's in road but not in lane. My third is in oval but not in round. My fourth is in hearing but not in sound. My whole is known as a sign of peace. And from Noah's ark won quick release.
What is common to eat before it's born and after it's dead?
I'm a large gray animal with a trunk and tusks. What am I?
What never gets any wetter no matter how hard it rains?