After Mrs. Tusk fattens the Hermit Crab, he tries to find a new shell, since he's too big. After ending up in Adam's locker and several attempts to get him out of there, Adam helps him find a new home. Meanwhile, Jake falls in love with a mermonkey.
- When Adam is holding Herman he says "stop pinching me ow that hurts" but he was wearing that huge metal helmet he wouldn't feel anything.
- David Coppertrout from "The Magic Fish" makes a brief, non-speaking cameo appearance in "The Little Mermonkey."
- (Adam walks on-screen with a bruised, red face) Adam: How are things going Jake? Jake: Terrible, my heart is broken. Adam : Well if it's any consolation, I feel terrible to. All the blood vessels in my face are broken. Jake: (referring to Herman) I told you that guy was trouble! Adam: Friends? Jake: Friends! (They hug)
- Jake Spidermonkey to a wet horse student: I said I was sorry! I thought for sure that you were an aquatic! Horse Student: Jerk! (Leaves off-screen) Jake: Well apparently, you can lead a horse to water, but you can't make him sink!