“Bart, take a letter. Dear Mr. Burns, I’m so glad you enjoyed my son’s blood, and your card was just great.” – Homer Simpson
Liver spots are one of those undeniable signs of aging that remind us and others that the robust younger years are far in the past. Mr. Burns, being very far indeed from his days as a barefoot boy with cheek of tan, has quite a lot of them, something The Simpsons liked to have fun with, most famously when Marge catches Burns coming out of the shower in “Brush with Greatness”. There’s another liver spot joke in Season 2, however, that’s so subtle that I doubt I noticed it for years after I first saw it. In “Blood Feud”, Homer angrily dictates a letter to Burns after receiving only a lousy card in exchange for saving the old man’s life:
You are a senile, buck-toothed old mummy, with bony girls arms, and you smell like an elephant’s butt!
Later, after Burns reads the letter and decides to have Homer fired, he’s ranting to Smithers about the contents: 
Senile, eh? Buck-toothed, am I? Bony arms, are they? Liver spots, did I?
Notice the addition? Homer doesn’t mention the liver spots; Burns does. It’s the show taking a quick, barely perceptible potshot at Burns that you really have to be paying attention to catch. Burns doesn’t just have liver spots, despite his fearsome visage, he’s actually sensitive about them.
charliesweatpants.com
(The crotch really does wear out too fast.)
Nice catch. It’s one of those great jokes that play double duty, in this case both as Burns’ self-image and senility at the same time.
And might I say it’s great to see a “Day of the Week” Cartoon post from you after so long.
Eek, that’s sum mighty nitpicking there. He’s not sensitive about smelling like an elephant’s butt (despite having that elephant’s head up the wall) for some reason.
I don’t think you know what nitpicking is. This is pointing out a well-hidden gag which shows the deeper level The Simpsons operated on.
Here’s an example of nitpicking: he shouts and slams his hands on the desk while reading the “elephant’s butt” line in the scene immediately before this one.
I don’t think this is a gag, that’s all. Maybe I’m not that bright. I don’t care.
Watching the 13th Season of Family Guy nonsense slowly destroys my brain.
It’s destroyed your ability to post under one name, that’s for sure.
It’s funnier to have troll follow me from post to post this way.
How do you work out I’m trolling you, rather than the other way round? By pointing out you jump from one username to another, including using mine for some reason?
Are you really that dumb you don’t even see the difference? Mouse over the avatar.
I love that he also shouts “Chinless, will you?” when nobody in the Simpsons universe has a chin, let alone him.
Bart has a cute tongue.
Here’s another gag: There’s a Triceratops head on the wall, next to the elephant.
Shit, that’s a good one. Nice eye.
fuck you
Here’s yet another gag: Lisa Simspon’s head resembles that of a Triceratops!