Melancholy

At the beginning of Act 4, I found the argument between Rosalind and Jaques very interesting. I especially found the different types of Melancholy that Jacques lists interesting (Scholar's, Musician's, Courtier's, Soldiers, and Lawyer's). Do you find these legitimate forms of melancholy (if melancholy has forms at all)? With this said, is there a type of melancholy for any occupation or hobby?