The Melon Collie meme is an image of a collie wearing a watermelon on its head. It is a literal and humorous interpretation of the 1995 Smashing Pumpkins album "Mellon Collie and the Infinite Sadness."
The play on words in the album title is the fact that "mellon collie" is a homophone – that is, words that sound alike – for "melancholy," which means sadness. The album is over 90 minutes long, contains 28 tracks and won seven Grammy awards, including Album of the Year. A collie is an intelligent dog with a herding instinct; the most famous collie was TV's Lassie.