Let's see what I remember of this one, albeit imperfectly.
Ernie is walking, and sees a ball on the wall. He picks up the ball, looks around, notices that there isn't anyone looking for it, so he decides to take this ball home with him.
HERRY: Hey Ernie, whatcha got there?
ERNIE: It's a ball.
H: What kind of ball?
E: (looks carefully at it) Why, it's a round ball.
H: So that ball is round. What else?
E: It's a large ball.
H: So that ball is round, and large. What else?
E: It's a yellow ball.
H: So that ball is round, and large, and yellow. What else?
E: It's kind of soft.
H: So that ball is round, and large, and yellow, and soft. What else?
E: Well that's all. The ball is round, large, yellow, and soft.
H: You're wrong. It's something else. That ball is round, and large, and yellow, and soft, and MINE! (as he yanks the ball away from Ernie)
E: (nervously) Oh gee... well, I'll see you (runs off)
H: HEY, WHERE ARE YOU GOING? Don't you wanna play "catch"?
[end of skit]